13. Propagation

Leaf-bud Cuttings

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Leaf-bud cuttings are used for many trailing vines and when space or cutting material is limited. Each node on a stem can be treated as a cutting. This type of cutting consists of a leaf blade, petiole, and a short piece of stem with an attached axillary bud. Place cuttings in the medium with the bud covered (¹⁄₂ to 1 inch) and the leaf exposed (Figure 4). Examples of plants that can be propagated in this manner include clematis, rhododendron, camellia, jade plant, rubber plant, devil’s ivy, grape ivy, dracaena, blackberry, mahonia, and heart-leaf philodendron.

Figure 4. Leaf-bud Cuttings.

Contributors

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Anthony V. LeBude, Associate Professor, Department of Horticultural Science

Frank A. Blazich, Distinguished Professor Emeritus, Department of Horticultural Science

Contribution by Extension Agents: Jessica Strickland, Mary Hollingsworth, Shawn Banks, Mack Johnson, Paige Patterson, Peg Godwin

Contributions by Extension Master Gardener Volunteers: Patty Brown, Renee Lampila, Jackie Weedon, Karen Damari, Connie Schultz

Lucy Bradley, Associate Professor and Extension Specialist, Urban Horticulture, NC State University; Director, NC State Extension Master Gardener program;

Kathleen Moore, Urban Horticulturist

Copy Editor: Barbara Scott

Based on text from the 1998 Extension Master Gardener manual prepared by:

Erv Evans, Extension Associate, Department of Horticulture Science

Frank A. Blazich, Professor, Department of Horticulture Science

How to cite this chapter:

LeBude, A.V., and F.A. Blazich. 2022. Propagation, Chapter 13. In: K.A. Moore, and. L.K. Bradley (eds). North Carolina Extension Gardener Handbook, 2nd ed. NC State Extension, Raleigh, NC. <http://content.ces.ncsu.edu/13-propagation>

For Further Reading

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• Bryant, G. 1995. Propagation Handbook. Stackpole Books: Mechanicsburg, Pennsylvania.
• Dirr, M. A. and C. W. Heuser, Jr. 1987. The Reference Manual of Woody Plant Propagation: From Seed to Tissue Culture. Varsity Press: Athens, Georgia.
• Hartmann, H. T., D. E. Kester, F. T. Davies and R. L. Geneve. 1996. Plant Propagation, Principles and Practices. 6th ed. Prentice Hall: Upper Saddle River, New Jersey.
• McMillan Browse, P. D. A. 1978. Plant Propagation. Simon and Schuster: New York.
• Toogood, A. 1993. Plant Propagation Made Easy. Timber Press: Portland, Oregon.

For Further Reading

Skip to For Further Reading

• Bryant, G. 1995. Propagation Handbook. Stackpole Books: Mechanicsburg, Pennsylvania.
• Dirr, M. A. and C. W. Heuser, Jr. 1987. The Reference Manual of Woody Plant Propagation: From Seed to Tissue Culture. Varsity Press: Athens, Georgia.
• Hartmann, H. T., D. E. Kester, F. T. Davies and R. L. Geneve. 1996. Plant Propagation, Principles and Practices. 6th ed. Prentice Hall: Upper Saddle River, New Jersey.
• McMillan Browse, P. D. A. 1978. Plant Propagation. Simon and Schuster: New York.
• Toogood, A. 1993. Plant Propagation Made Easy. Timber Press: Portland, Oregon.

Cane Cuttings

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Cane cuttings provide an easy way to propagate some overgrown, leggy house plants such as dumbcane, corn plant, Chinese evergreen, and other plants with thick stems. Leafless stem sections (2 to 3 inches long) are cut from older stems. Each cane should have one or two nodes (Figure 5). Lay the cutting horizontally on the medium, or insert it vertically with about half of the cutting below the surface of the medium, and leave a bud facing upward. Cane cuttings are usually potted when roots and new shoots appear.

Figure 5. Cane Cuttings.

Split-vein

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Detach a leaf from a rex begonia and remove the petiole. Make cuts on several prominent veins on the underside of the leaf (Figure 3). Lay the cutting, lower side down, on the medium. If the leaf curls up, hold it in place by covering the margins with rooting medium. New plants will form at each cut. A variation of this method is to cut the leaf into wedges, so that each piece has a main vein. The leaf wedge should be inserted into the media with the main vein partially covered.

Figure 3. Split-vein.

Cacti and Succulents

• Do not moisten the potting soil at first (i.e., place the cutting in a pot of dry potting soil).
• Do not cover the cutting with a mini-greenhouse.

Only when you see signs of growth, which can take several weeks if not months for cacti and succulents, should you start watering them.

Root Cutting

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Some plants can be propagated from a section of a root. Root cuttings of woody plants are usually taken from plants during the dormant season, when carbohydrate levels are high. Root cuttings of some species produce new shoots, which then form their own root system, whereas root cuttings of other plants develop root systems before producing new shoots. Examples of plants that can be propagated from root cuttings include raspberry, blackberry, rose, trumpet vine, phlox, crabapple, fig, lilac, and sumac.

Plants with large roots are normally propagated outdoors. The root cuttings should be 2 to 6 inches long. Make a straight cut on the proximal end (nearest the crown of the parent plant) and a slanted cut on the distal end (furthest from the crown) of each root cutting. Tie the cuttings in bundles with all the same type ends together. It is important to maintain the correct polarity of the cuttings. Store for 3 weeks in moist sawdust, peat moss, or sand at 40°F. Remove from storage. Space the cuttings about 2 to 3 inches apart in well-prepared garden soil. The tops of the cuttings (proximal ends) should be 2 to 3 inches below the soil surface.

For plants with small roots, cut the roots into 1 to 2 inch sections. Lay the cuttings horizontally on the medium surface in a flat and cover with about ¹⁄₂ inch of soil or sand. Place the flat inside a plastic bag or cover with a pane of glass. Place the flat in the shade and remove the protective cover after new shoots appear.

Leaf-petiole

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Remove a leaf and include up to 1¹⁄₂ inches of the petiole. Insert the lower end of the petiole into the medium (Figure 1). One or more new plants will form at the base of the petiole. The new plants are then severed from the original leaf-petiole cutting and the cutting may be used once again to produce more plants. Examples of plants that can be propagated by leaf-petiole cuttings include African violet, peperomia, episcia, hoya, and sedum.

Figure 1. Leaf-petiole.

Types of Stem Cuttings

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Herbaceous cuttings are made from non-woody, herbaceous plants such as coleus, chrysanthemums, and dahlia. A 3- to 5-inch piece of stem is cut from the parent plant. The leaves on the lower one-third to one-half of the stem are removed. A high percentage of the cuttings root, and they do so quickly.

Softwood cuttings are prepared from soft, succulent, new growth of woody plants, just as it begins to harden (mature). Shoots are suitable for making softwood cuttings when they can be snapped easily when bent and when they still have a gradation of leaf size (oldest leaves are mature while newest leaves are still small). For most woody plants, this stage occurs in May, June, or July. The soft shoots are quite tender, and extra care must be taken to keep them from drying out. The extra effort pays off, because they root quickly.

Semi-hardwood cuttings are usually prepared from partially mature wood of the current season’s growth, just after a flush of growth. This type of cutting normally is made from mid-July to early fall. The wood is reasonably firm and the leaves of mature size. Many broadleaf evergreen shrubs and some conifers are propagated by this method.

Hardwood cuttings are taken from dormant, mature stems in late fall, winter, or early spring. Plants generally are fully dormant with no obvious signs of active growth. The wood is firm and does not bend easily. Hardwood cuttings are used most often for deciduous shrubs but can be used for many evergreens. Examples of plants propagated at the hardwood stage include forsythia, privet, fig, grape, and spirea.

The three types of hardwood cuttings are straight, mallet, and heel (Figure 3). A straight cutting is the most commonly used stem cutting. Mallet and heel cuttings are used for plants that might otherwise be more difficult to root. For the heel cutting, a small section of older wood is included at the base of the cutting. For the mallet cutting, an entire section of older stem wood is included.

Figure 3. The three types of hardwood cuttings are straight, mallet, and heel.

Leaf without a Petiole

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This method is used for plants with thick, fleshy leaves. The snake plant (Sansevieria), a monocot, can be propagated by cutting the long leaves into 3- to 4-inch pieces. Insert the cuttings vertically into the medium. African violet, a dicot, can also be propagated from the leaf blade itself. Cut a leaf from a plant and remove the petiole. Insert the leaf vertically into the medium making sure that the midvein is buried in the rooting medium (Figure 2). New plant(s) will form from the midvein.

Figure 2. Leaf without a petiol.

Stem Cuttings Step by Step

Cuttings succeed more readily when the plant is actively growing, therefore in spring and summer. Rooting is slower and the failure rate is greater on cuttings taken in late fall or early winter, when days are short. We are therefore entering “cutting season,” at least when it comes to houseplants. In early March in the Northern Hemisphere, indoor plants are just starting to emerge from their winter torpor thanks to the longer and longer days.

1. Start by preparing the container you’ll use for the cutting. A classic plastic flowerpot would work perfectly, but you can also recycle a yogurt tub or other container. Of course, you’ll have to punch drainage holes into the bottom of pots that don’t have any. Avoid large pots, as the soil there tends to stay soggy for extended periods. Plants root better in small pots about 2 ½ to 4 in (6 to 10 cm) in diameter, as they allow the soil to dry out a little more quickly and that increases air circulation to the roots that are forming. Alternatively, you can also put several cuttings in a larger pot or tray, preferably a shallow one.

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Woman fills a small seedling pot with soil with a shovel. Preparation for planting seedlings at home. Gardening, growing vegetables and herbs for food.

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2. Fill the pot with potting soil. That can be “houseplant soil” or “seed-starting soil” or just perlite or vermiculite. Avoid garden soil and even compost, as you’ll want the most sterile potting soil possible.
3. Moisten the soil well and allow any excess water to drain away.

4. Using a pencil or pen, punch a hole in the potting soil in the center of the pot: the hole you’ll be slipping the cutting into.

5. Now take a section of healthy stem using a sharp knife or pruner. Make sure it has at least three nodes and preferably four or five. (A node is the place on the stem where leaves are attached or were previously attached.)

6. Remove flower buds and flowers (they’ll sap the energy of the cutting if you leave them on). You should also remove any lower leaves that will be covered in soil. There should be enough bare stem so that at least 2 nodes can be covered.

7. For plants that you want to see branch profusely, such as coleus and hibiscus, pinch off the tip of the cutting. This stimulates it to produce several new stems rather than just one. For plants where a single stem is the desired form (dieffenbachias, dracaenas, yuccas, etc.), pinching isn’t necessary.

8. Easy-to-root plants include philodendrons, coleus, pileas and begonias. All have soft, green stems with no woody bark and root readily. Woody plants, such as hibiscus, dracaenas and crotons, are more difficult. They root more slowly and the risk of failure is greater. For these plants, buy a root hormone (available in garden centers). Using a cotton swab, brush this product on the lower part of the cutting. The hormone will stimulate those recalcitrant stems to produce roots.
9. Slip the cutting, bottom part down, of course, into the previously prepared hole, to the second or third node. Gently tamp the potting soil so that the cutting stands upright. (For a very large cutting, a stake may be needed to solidify it.)

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417.K

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10. The vast majority of cuttings root best in high humidity and so should be rooted under glass. After all, fresh cuttings don’t yet have roots and when they lose water to evaporation, can’t readily replace the moisture they have lost. If the air is dry, they therefore lose water very quickly, especially thin-leaved species. However, if you place the cuttings under a clear plastic dome or inside a clear plastic bag (“under glass” or “in a mni-greenhouse” in gardening parlance), the air will remain very humid. Indeed, the humidity level in such a structure is often near 100%!
    As a result, the cutting won’t lose moisture through transpiration, giving it a better chance of recovery. So, do cover your cuttings with a dome or a transparent plastic bag*.

*Yes, you can seal the plastic bag. Plants breathe perfectly well inside sealed containers. There is no need to “leave an opening” so the plant won’t suffocate!

11. Place the pot in a well-lit location, but out of direct sunlight, and also in a relatively warm spot (21–24°C). A heating mat can be useful if the room is cool.
12. At this point, there’ll be a bit of a wait until rooting occurs. Some cuttings root very quickly (coleus in just four to seven days!), but others can take two or three weeks. Many woody cuttings take from 1 to 6 months!

You’ll know the cutting is successful when you see new leaves beginning to appear, a sign that the roots are starting to do their job. At that point, give the cutting a bit of a tug: if there is resistance, it has rooted. You can then remove the mini-greenhouse and place the plant (it is no longer a cutting) in a place suitable for its needs, treating it like an adult plant.

Yes, you have successfully grown a plant from a cutting! Now, that wasn’t hard, was it?

What to Cut?

Several parts of a plant can be used to produce cuttings.

Some plants (especially weeds such as quackgrass and Japanese knotweed) have the ability to regrow from a section of root or rhizome placed or left in the ground (this is called a root cutting). Still, the ability to sprout from root cuttings remains relatively rare.

The same goes for leaf cuttings, where you grow an entire new plant from a single leaf. This is only possible with very few plants, such as African violets, crassulas and sansevieras.

On the other hand, stem cuttings, where you root a section of the plant’s stem, are possible with almost any plant that produces stems: houseplants, shrubs, trees, perennials, conifers, climbers and many more.

Objectives

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This chapter teaches people to:

• Understand the basic principles of sexual and asexual propagation.
• Be familiar with common methods of sexually and asexually propagating plants.
• Know the recommended timing for propagating plants.

Sexual Propagation

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Seeds

Most seeds are composed of three major parts: embryo, endosperm (food storage) tissue, and a seed coat (protective tissue) (Figure 13–1). The embryo is a miniature plant in a resting (dormant) state. Most seeds contain a built-in food supply called the endosperm. The protective outer covering of a seed is called the seed coat. It protects seeds from mechanical injury and from diseases and insects. Also, the seed coat usually prevents water from entering the seed until time to germinate. The seed coat in many cases allows seeds to be stored for extended periods. The seed leaves, cotyledons, differ in shape from the true leaves. Monocots (such as corn) produce only one cotyledon; dicots (like beans) produce two cotyledons (Figure 13–2). Some gymnosperms, like pines, have many cotyledons.

To obtain vigorous plants from seeds, start with high-quality seeds from a reliable source. Select cultivars that provide the desired size, color, and growth habit. Choose cultivars adapted to your area. Many vegetable and flower cultivars are hybrids that may cost more than open-pollinated types, but they usually have more vigor, more uniformity, and better growth than nonhybrids.

Purchase only enough seed for one year because the likelihood of germination decreases with age. The seed packet label usually indicates essential information about the cultivar or species, such as the year in which the seeds were packaged, the germination percentage, and whether the seeds have received any chemical treatment.

If seeds are obtained well ahead of the actual sowing date (or are surplus seeds), store them in a cool, dry place. Laminated or foil packages help ensure dry storage. Paper packets are best kept in tightly sealed containers and maintained around 40°F in low humidity. A good storage location would be an airtight jar in the refrigerator. Gardeners can save money and cultivate a rewarding hobby by saving seeds from plants in their own gardens. Seeds that have been produced through insect, animal or wind, or other natural pollination methods are known as open-pollinated. Open-pollination can increase biodiversity, and plants may display different characteristics than the parent plants. This is especially true when saving seed from hybrids.

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Table 13–1. Germination information for selected plants.

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Germination

Germination is the resumption of active embryo growth after a dormant period. Three conditions must be satisfied for a seed to germinate:

• The seed must be viable; that is, the embryo must be alive and capable of germination.
• Internal conditions of the seed must be favorable for germination; that is, any physical, chemical, or physiological barriers to germination must have disappeared or must have been removed by the propagator.
• The seed must be subjected to appropriate environmental conditions, including water (moisture), proper temperature, oxygen, and, for some species, light (Table 13–1).

The first step in germination is absorption of water. An adequate, continuous supply of moisture is important to ensure germination. Once germination has begun, a dry period can kill the embryo.

Light can stimulate or inhibit seed germination of some species. Plants that require light for germination include ageratum, begonia, browallia, impatiens, lettuce, and petunia. Other plants germinate best in the dark. These include calendula, centaurea, phlox, and verbena. Some plants germinate in either light or dark. Seed catalogs and seed packets often list germination and cultural information for particular plants. When sowing light­-requiring seeds, sow them on the soil surface. Supplemental light can be provided by fluorescent fixtures suspended 6 to 12 inches above the soil surface for 16 hours a day.

Respiration in dormant seeds is low, but they do require some oxygen. Respiration rate increases during germination. The medium in which the seeds are sown should be loose and well aerated. If the oxygen supply during germination is limited or reduced, germination can be severely retarded or inhibited.

Temperature affects the germination percentage and the rate (speed) of germination. Some seeds germinate over a wide range of temperatures; others have a narrow range. Many species have minimum, maximum, and optimum temperatures at which they germinate. For example, tomato seeds have a minimum germination of 50°F, a maximum of 95°F, and an optimum germination temperature of 80°F. When germination temperatures are listed, they are usually optimum temperatures. For most plants, 65 to 75°F is best.

Seed Dormancy

Viable seeds that do not germinate are dormant. Dormancy can be regulated by the environment or by the seed itself. If a seed is not exposed to sufficient moisture, proper temperature, oxygen, or for some species, light, the seed will not germinate. In this case, the seed’s dormancy is caused by unfavorable environmental conditions.

Some seeds may not germinate because of some inhibitory factor of the seed itself. This kind of dormancy consists of two general types: (a) seed coat (or external) dormancy and (b) internal (endogenous) dormancy. A seed can also exhibit both kinds of dormancy.

Techniques to Break Dormancy

Seed Scarification

External dormancy results when a seed’s hard seed coat is impervious to water and gases. The seed will not germinate until the seed coat is altered physically. Any process of breaking, scratching, or mechanically altering the seed coat to make it permeable to water and gases is known as scarification. In nature this may occur during the winter, when freezing temperatures crack the seed coat or while microbial activities modify the seed coat as the seed lies in the soil. Scarification may also occur as the seed passes through the digestive tract of an animal.

Scarification can be forced, rather than waiting for nature to alter the seed coats. Commercial growers scarify seeds by soaking them in concentrated sulfuric acid. Seeds are placed in a glass container, covered with sulfuric acid, gently stirred, and allowed to soak for 10 minutes to several hours, depending on the species.

Reference books give appropriate concentrations and durations. When the seed coat has been modified (thinned), the seeds are removed, washed, and sown. Sulfuric acid can, however, be very dangerous for an inexperienced individual and should be used with extreme caution. Vinegar is safer and can be used for some species; the technique is the same as with sulfuric acid.

With mechanical scarification, seeds are filed with a metal file, rubbed with sandpaper, or cracked gently with a hammer to weaken (break) the seed coat. Another method is hot water scarification. Bring water to a boil (212°F), remove the pot from the stove, and place the seeds into the water. Soak the seeds until the water cools; then remove them and let them dry.

Seed Stratification

The second type of imposed dormancy, internal dormancy, is regulated by the inner seed tissues. This dormancy prevents seeds of many species from germinating when environmental conditions are not favorable for survival of the seedlings. There are several different types of internal dormancy. «Shallow» dormancy, displayed by many vegetable seeds, simply disappears with dry storage. No special treatment is necessary. However, other types require a particular duration of moist-chilling or moist-­warming periods, or both.

Cold stratification (moist-chilling) involves mixing seeds with an equal volume of a moist medium (sand or peat, for example) in a closed container and storing them in a refrigerator. Periodically, check to see that the medium is moist but not wet. The length of time required to break (remove) dormancy varies by species; check reference books for recommended times. This type of dormancy may be satisfied naturally if seeds are sown outdoors in the fall. Warm stratification is similar except temperatures are maintained at 68 to 86°F depending on the species.

Growing Plants from Seeds

Media

A wide range of media can be used to germinate seeds. With experience, you will learn to determine what works best for you. The germinating medium should be fine and uniform yet well aerated and loose. It should be free of insects, disease organisms, nematodes, weeds, and weed seeds. It should also be of low fertility and capable of holding moisture but be well drained. Purchase commercial potting media containing fine-particle pine bark, sphagnum peat moss, and perlite, or prepare a combination of equal parts (by volume) of these materials. Do not use garden (mineral) soil to start seedlings; it is not sterile, it is too heavy, and it does not drain well. Soil mixes have little fertility, so seedlings must be watered with a dilute fertilizer solution soon after germination and emergence.

Containers

Plastic cell packs can be purchased or reused if sterilized. In this system, each cell holds a single plant. This method reduces the risk of root injury when transplanting. Peat pellets, peat pots, or expanded foam cubes can also be used for producing seedlings. Resourceful gardeners often use cottage cheese containers, the bottoms of milk cartons, bleach containers, or pie pans. Just make certain that adequate drainage holes are made in the bottoms of the containers and that the containers are sterile.

The importance of using sterile medium and containers cannot be overemphasized. Before using the containers, wash them to remove any debris, immerse them in a fresh solution of one part chlorine bleach to nine parts water for five minutes, and allow them to dry.

Sowing Seeds

For medium and large seeds, make furrows 1 to 2 inches apart and ¹⁄₈-inch to ¹⁄₄-inch deep across the surface of the planting medium. Sowing in rows improves light and air movement. If damping-off disease occurs, there is less chance of it spreading. Seedlings in rows are easier to label and handle at transplanting time than those that have resulted from broadcasting seeds. Sow the seeds thinly and uniformly in the rows by gently tapping the packet of seed. Cover the seeds lightly; a suitable planting depth is usually about two to four times the minimum diameter of the seeds.

Extremely fine seeds such as carrot, petunia, and snapdragon should not be covered, but simply dusted on the surface of the germinating medium and watered with a fine mist. If these seeds are broadcast, strive for a uniform stand by sowing half the seeds in one direction, then sowing the remaining seeds in the other direction.

Large seeds are frequently sown directly in a small container or cell pack, which eliminates the need for early transplanting. Usually, sow two or three seeds per cell. Later, thin them to allow only the most vigorous seedling per cell to grow.

Most garden stores and seed catalogs offer indoor and outdoor seed tapes. Seed tapes have precisely spaced seeds enclosed in an organic, water-soluble material. When planted, the tape dissolves and the seeds germinate normally. Seed tapes are convenient for extremely small, hard-to-handle seeds. Seed tapes allow uniform emergence, eliminate overcrowding, and permit sowing in perfectly straight rows. The tapes can be cut at any point for multiple row plantings, and thinning is rarely necessary. Tapes are more expensive per seed.

Water and Light

Moisten the planting medium thoroughly before planting. After seeding, spray with a fine mist or place the containers in a pan or tray that contains about 1 inch of warm water. Avoid splashing or excessive flooding, which might displace small seeds. When the planting mix is saturated, set the container aside to drain. The soil should be moist but not overly wet.

The seed flats should remain sufficiently moist during the germination period. Excessive moisture, however, can lead to damping-off or other disease or insect problems. Place the whole flat or pot into a clear plastic bag to maintain moisture. The plastic should be at least 1 inch above the soil. Keep the container out of direct sunlight; otherwise, the temperature may increase and injure the seeds. Many home gardeners cover their flats with panes of glass instead of using a plastic bag. Be sure to remove the plastic bag or glass cover when the first seedlings emerge.

After the seeds have germinated, move the flats to a well-lighted location; the temperature should be 65 to 70°F during the day and 55°F to 60°F at night. This prevents soft, leggy growth and minimizes disease problems. Some crops, of course, may grow best at different temperatures.

Seedlings must receive bright light after germination. Place them in a south-facing window. If a large, bright location is not available, place the seedlings under fluorescent lights. Use two 40-watt, cool-white fluorescent tubes or special plant growth lamps. Position the plants 6 inches below the light source and provide 16 hours of light daily. As the seedlings grow, the lights should be raised. A more detailed discussion of lighting is covered in chapter 18, «Plants Grown in Containers.»

Transplanting Seedlings

Plants not seeded individually must eventually be transplanted into their own containers as seedlings to give them proper growing space. A common mistake is to leave the seedlings in the flat too long. The ideal time to transplant young seedlings is when the first true leaves appear.

Dig up the small plants carefully with a knife or plant label. Let the group of seedlings fall apart and pick out individual plants. Gently ease them apart to avoid root injury in the process. Handle small seedlings by their leaves, not their delicate stems (Figure 13–3). Using a small tool or your finger, punch a hole in the medium. Plant a seedling at the same depth at which it was growing in the seed flat. Firm the soil and water gently. Keep newly transplanted seedlings in the shade for a few days, or place them under fluorescent lights. Locate them away from sources of direct heat. Continue watering and fertilizing as in the seed flats.

Containers for seedlings should be economical, durable, and make efficient use of available space. Individual pots or plastic cell packs can be used. Another possibility is compressed peat pellets, which expand to form compact individual pots when soaked in water.

They waste no space, do not fall apart as easily as peat pots, and can be set out directly in the garden. If you wish to avoid transplanting seedlings altogether, compressed peat pellets are excellent for direct sowing.

When setting plants outdoors that were grown in peat pots, be sure to break the sides of the pot and to cover the pot completely. If the top edge of the peat pot extends above the soil level, it may act as a wick and draw water away from the soil in the pot. Tear off the top lip of the pot and plant flush with the soil surface.

Examples of Seed Treatments

Camellia—Collect and plant in the fall before the seed coat hardens. If seeds are dry, soak them in warm water for 24 hours before planting. Some people pre-chill the seeds until radicle emergence and then plant the sprouted seeds.

Crabapple—Collect fruits as they begin to soften and when the seeds are brown. Remove the fruit pulp. Provide one to four months of cold-moist stratification. Seeds will germinate in 30 to 60 days.

Dogwood—Collect fruits (drupes) when they are red and when seeds are mature; if collection is delayed too long, birds may eat the fruit. Remove the pulp, clean, and air dry, then moist-chill them in a refrigerator for three to four months. Seeds can be planted in the fall, but they will not germinate until spring.

Goldenrain tree—Collect fruits when capsules turn brown but before they open. Extract seeds, dry, and store. Seed coats are very hard, and seeds will require scarification before germination.

Holly—Germinating holly seeds can be very difficult and extremely slow. It may take two to three years because of the holly’s hard seed coat and an immature (rudimentary) embryo.

Maple—Variation in dormancy exists with different species of maples. Spring-maturing seeds of species such as red and silver maple should be collected immediately when mature, not permitted to dry, and sown immediately. For seeds of other maple species that mature in the fall, such as southern sugar maple, stratification for 90 to 120 days is necessary.

Oak—Acorns of white oak do not become dormant. When planted in the fall, roots will emerge during winter; shoots will emerge in the spring. On the other hand, acorns of black oak germinate best if stratified for one to three months (if not planted in the fall). Acorns of red oaks should be planted in the fall or stratified for one to three months. Check references for individual species.

Southern magnolia—Remove the fleshy pulp from around the seeds. Moist pre-chilling for two to four months is needed unless planted in the fall.

Figure 13–1. The three parts to a seed: 1. The protective tissue or seed coat 2. The embryo which grows into a new plant. 3. The endosperm which is the nutritive or food storage, supplying nutrients to the embryo.

Figure 13–2. Seed germination of a dicot seedling.

Figure 13–3. Remove seedlings from the tray and place them in a pile. Tease individuals out gently holding them by their leaves.

Further Reading

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Beyl, Caula A. and Robert N. Trigiano, eds. Plant Propagation: Concepts and Laboratory Exercises. Boca Raton, Florida: CRC Press, 2008. Print.

Bir, Richard E. Growing and Propagating Showy Native Woody Plants. Chapel Hill, North Carolina: The University Of North Carolina Press, 1992. Print.

Bonner, Franklin T. and Robert P. Karrfalt, eds. The Woody Plant Seed Manual. Washington, DC: United States Department of Agriculture Forest Service, 2008. Print and PDF file. Agriculture Handbook 727.

Bryant, Geoff. Propagation Handbook: Basic Techniques for Gardeners. Mechanicsburg, Pennsylvania: Stackpole Books, 1995. Print.

Dirr, Michael A. Manual of Woody Landscape Plants: Their Identification, Ornamental Characteristics, Culture, Propogation and Uses. 6^th ed. Champaign, Illinois: Stipes Publishing L.L.C., 2009. Print.

Hartmann, Hudson T., et al.. Hartmann & Kester’s Plant Propagation: Principles and Practices. 8^th ed. Upper Saddle River, New Jersey: Prentice Hall, Inc., 2010. Print.

Hill, Lewis. Secrets of Plant Propagation: Starting Your Own Flowers, Vegetables, Fruits, Berries, Shrubs, Trees, and Houseplants. North Adams, Massachusetts: Story Publishing, 1985. Print.

Phillips, Harry R. Growing and Propagating Wild Flowers. Chapel Hill, North Carolina: The University of North Carolina Press, 1985. Print.

Royal Horticultural Society Propagation Techniques. London: Octopus Publishing Group Ltd, 2013. Print.

Thompson, Peter. Creative Propagation. 2^nd ed. Portland, Oregon: Timber Press, Inc., 2005. Print.

Toogood, Alan, ed. American Horticultural Society Plant Propagation: The Fully Illustrated Plant-by-Plant Manual of Practical Techniques. New York: DK Publishing, Inc., 1999. Print.

This is the perfect time of year to take new pliable tip cuttings from your perennial herbs to make root cuttings.

If you are fortunate enough to have a friend who grows herbs, you might want to try rooting some cuttings of perennial herbs, a quick and inexpensive way to obtain plants that are true to type. The best time to do this is in the spring when plants are putting out new growth.

     Choose sturdy cuttings, three to four inches long, and remove the leaves from the lower half of the stem. If the stems are very woody-like rosemary or sage or winter savory-use a sharp knife to strike (gently yet firmly scrape off the woody cambium layer in one clean stroke) on just one side of the stem. My gardening friend, Kathleen Connole, who does most of the root cuttings at the Ozark Folk Center’s greenhouse, says that this stimulates the cells to go into another mode than producing leaf growth-and produce roots.

Fill small plastic pots with a medium like Promix ™ or combine half sterile potting mix (spaghnum) and half perlite. Dampen the mix thoroughly. Dip the leafless part of each stem in a rooting powder, such as Rootone™, shake off the excess, and place the stem in the moist medium. The Rootone is not absolutely necessary; it is a fungicide. Mist the cuttings.

     Keep the cuttings in a warm place with filtered sun. Mist them several times a day, keeping the foliage damp. They should not be allowed to dry out. If the cuttings dry out and wither in the first two or three weeks, they will not root.

     The cuttings should produce a healthy root system in six weeks or less. After this time the stems should show signs of new growth, and if tugged gently, their new roots should hold them in the soil. If all danger of frost is past, you can now transplant the herbs to new pots or into the garden.

Root cuttings can also be done in water. They need a little more attention in that the water should be changed daily, or at least every other day, and the roots rinsed. Some plants root better in water than others and some won’t root in water. Thick-stemmed plants often root better in water and mints and basil root quickly as water cuttings. Both Kathleen and I agree that water root cuttings are not as strong and are trickier to transplant into soil. However, Kathleen is very successful with rooting Confederate roses and artemisia in water.

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Frequently Asked Questions

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1. When should I collect oak acorns and other shade tree seeds to grow them, and how should I handle the seeds to get them to germinate?

2. My jade plant is dying. Can I propagate it and keep it alive?

Cuttings from healthy plants work best; sometimes, cuttings from plants that are struggling will not take root so it may not be possible to propagate it. If you would like to try, jade plants are propagated by stem or leaf cuttings. If it is a variegated jade, use a stem cutting to ensure you are preserving the genetic material that leads to the variation in leaf color.

3. I planted seeds for some annual flowers, but none of them came up. Why?

There could be several reasons your seeds failed to germinate.

• The seeds were never viable.
• They were planted too deep or too shallow.
• The seedbed was kept too wet or too dry.
• They died shortly after germinating.
• The seeds or seedlings were eaten by an insect or animal.
• The seeds or seedlings were killed by a disease.
• A weather event such as frost killed the seedlings.

4. How do I propagate azaleas?

One of the most reliable ways to propagate azaleas is to layer some of the lower branches in the soil and weigh them down with a brick (wounding and applying a rooting hormone also helps the process). If cuttings are to be used, best success is achieved on evergreen azaleas with semi-hardwood cuttings (they break with a snap), taken late June through August. Again, wounding the lower stems and applying a rooting hormone increases success rates. Be sure to use a well-drained medium and provide partial shade. Roots should form in four to six weeks. These Horticulture Information Leaflets from NC State Extension are excellent references: HIL 8701, Plant Propagation by Layering: Instructions For the Home Gardener, and HIL 8702, Plant Propagation by Stem Cuttings: Instructions For the Home Gardener.

5. My irises are about 10 years old, and they are not blooming well any more. What is wrong with them?

*To read other chapters in the North Carolina Extension Gardener Handbook see the Table of Contents. If you have questions about this chapter contact your local NC State Extension expert at your local Cooperative Extension Center.

Procedures for Rooting Stem Cuttings

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Cuttings should generally consist of the current or past season’s growth. Avoid material with flower buds if possible. Remove any flowers and flower buds when preparing cuttings so the cutting’s energy can be used in producing new roots rather than flowers. Take cuttings from healthy, disease-free plants, preferably from the upper part of the plant.

The fertility status of the stock (parent) plant can influence rooting. Avoid taking cuttings from plants that show symptoms of mineral nutrient deficiency. Conversely, plants that have been fertilized heavily, particularly with nitrogen, may not root well. The stock plant should not be under moisture stress. In general, cuttings taken from young plants root in higher percentages than cuttings taken from older, more mature plants. Cuttings from lateral shoots often root better than cuttings from terminal shoots.

Early morning is the best time to take cuttings, because the plant is fully turgid. It is important to keep the cuttings cool and moist until they are stuck. An ice chest or dark plastic bag with wet paper towels may be used to store cuttings. If there will be a delay in sticking cuttings, store them in a plastic bag in a refrigerator.

While terminal parts of the stem are best, a long shoot can be divided into several cuttings. Cuttings are generally 4 to 6 inches long. Use a sharp, thin-bladed pocket knife or sharp pruning shears. If necessary, dip the cutting tool in rubbing alcohol or a mixture of 1 part bleach to 9 parts water to prevent transmitting diseases from infected plant parts to healthy ones.

Remove the leaves from the lower one-third to one-half of the cutting (Figure 4). On large-leafed plants, the remaining leaves may be cut in half to reduce water loss and conserve space. Species difficult to root should be wounded.

Treating cuttings with root-promoting compounds can be a valuable tool in stimulating rooting of some plants that might otherwise be difficult to root. Prevent possible contamination of the entire supply of rooting hormone by putting some in a separate container before treating cuttings. Any material that remains after treatment should be discarded and not returned to the original container. Be sure to tap the cuttings to remove excess hormone when using a powder formulation.

The rooting medium should be sterile, low in fertility, and well-drained to provide sufficient aeration. It should also retain enough moisture so that watering does not have to be done too frequently. Materials commonly used are coarse sand, a mixture of one part peat and one part perlite (by volume), or one part peat and one part sand (by volume). Vermiculite by itself is not recommended, because it compacts and tends to hold too much moisture. Media should be watered while being used.

Insert the cuttings one-third to one-half their length into the medium. Maintain the vertical orientation of the stem (do not insert the cuttings upside down). Make sure the buds are pointed up. Space cuttings just far enough apart to allow all leaves to receive sunlight. Water again after inserting the cuttings if the containers or frames are 3 or more inches in depth. Cover the cuttings with plastic and place in indirect light. Avoid direct sun. Keep the medium moist until the cuttings have rooted. Rooting will be improved if the cuttings are misted on a regular basis.

Rooting time varies with the type of cutting, the species being rooted, and environmental conditions. Conifers require more time than broadleaf plants. Late fall or early winter is a good time to root conifers. Once rooted, they may be left in the rooting structure until spring.

Newly rooted cuttings should not be transplanted directly into the landscape. Instead, transplant them into containers or into a bed. Growing them to a larger size before transplanting to a permanent location will increase the chances for survival.

Figure 4. Remove the leaves from the lower one-third to one-half of the cutting.

Hardening Plants

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Hardening is the process of conditioning a plant for growth outdoors. If plants produced inside are planted outdoors without a hardening period, their growth could be severely limited. Hardening is most critical with early crops, when adverse climatic conditions can be expected.

Hardening is accomplished by decreasing temperature and relative humidity gradually, and reducing water. This procedure results in the accumulation of carbohydrates and thickening of cell walls. A change from a soft, succulent type of growth to a firmer, harder type is desired.

The process should be started at least two weeks before plants are to be planted in the garden. Place seedlings outside in a protected area on warm days (Figure 13–23). Increase the length of exposure gradually. Do not put tender seedlings outdoors on windy days or when temperatures are below 45°F. Even cold-hardy plants will be injured if exposed to freezing temperatures before they are hardened.

The hardening process is intended to slow plant growth. Carried to an extreme, however, hardening can cause significant damage. For example, cauliflower produces thumb-sized heads and fails to develop further if hardened too severely; cucumbers and melons stop growing entirely.

Genetically Modified Organisms (GMOs)

Figure 13–23. Tomatoes hardening off under cover and near the wall of a building.

Cristina Sanvito, Flickr

 CC BY 2.0

Figure 13–24. Organic labeling.

Figure 13–25. New plants are forming at the base of these rooted hens and chicks (Echeveria spp.) leaves.

Kathleen Moore

 CC BY 2.0

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Asexual Propagation Cuttings

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Asexual propagation is the process of taking vegetative pieces of a desirable plant and reproducing new plants from these tissues. Asexual propagation permits cloning of plants, meaning the resulting plants are genetically identical to the parent plant. The major methods of asexual propagation are cuttings, layering, division, separation, budding, grafting, and micropropagation (tissue culture).

CUTTINGS

Propagation by cuttings involves rooting a severed piece of the parent plant or, in some cases, producing new plants from severed pieces of tissue (leaf cuttings). A greenhouse is not necessary for successful propagation by cuttings.

If rooting only a few cuttings, you can use a flowerpot or small flat (Figure 13–4). Maintain high humidity by covering the cuttings with a bottomless milk jug or by placing the container into a clear plastic bag. Cuttings can also be placed in plastic trays covered with clear plastic stretched over a wire frame.

Containers must have holes in the bottoms for drainage. The plastic helps keep the humidity high and reduces water loss from the plant. If a more elaborate structure is needed, construct a small hoop frame or use an intermittent mist system. NC State Extension publication AG-426, A Small Backyard Greenhouse for the Home Gardener, may be helpful.

The rooting medium should be sterile, low in fertility, well drained to provide sufficient aeration, and moisture-retentive so that watering does not have to be done too frequently. Materials commonly used are coarse sand, a mixture of one part peat and one or two parts perlite (by volume), or one part peat and one part sand (by volume). Various commercial potting media may also be used. Vermiculite by itself is not recommended because it packs and tends to hold too much moisture. Media should be watered well before use.

There are several different kinds of cuttings. Which type you use depends on the kind of plant and, often, the plant’s growth stage.

Some plants can be propagated from only a leaf, but most plants produce only a few roots or simply decay. Because leaf cuttings do not include an axillary bud, they can be used only for plants that are capable of forming adventitious buds. Leaf cuttings are used almost exclusively for propagating some indoor plants.

Leaf Cuttings

Leaf petiole—Remove a leaf and include up to 1½-inches of the petiole. Insert the lower end of the petiole into the medium (Figure 13–5). One or more new plants form at the base of the petiole. The leaf may be severed from the new plants—when they have their own roots—and then reused. Examples of plants that can be propagated by this method include African violet, peperomia, episcia, hoya, and sedum.

Leaf without a petiole—This method is used for plants with thick, fleshy leaves. The snake plant (Sansevieria trifasciata), a monocot, can be propagated by cutting the long leaves into 3-inch to 4-inch pieces (Figure 13–6). Insert the cuttings vertically into the medium. African violets (dicot) can also be propagated this way. Cut a leaf from a plant and remove the petiole. Insert the leaf vertically into the medium, making sure that the midvein is buried in the rooting medium. New plants form from the midvein.

Split-vein—Detach a leaf from the plant and remove the petiole. Make cuts on several prominent veins on the underside of the leaf (Figure 13–7). Lay the cutting, lower side down, on the medium. New plants form at each cut. If the leaf curls up, hold it in place by covering the margins with rooting medium. A variation of this method is to cut the leaf into wedges so that each piece has a main vein.

Leaf-Bud Cuttings

Leaf-bud cuttings are used for many trailing vines and when space or cutting material is limited. Each node on a stem can be treated as a cutting. The cutting consists of a leaf blade, petiole, and a short piece of stem with an attached axillary bud. Place cuttings in the medium with the bud covered (to 1 inch) and the leaf exposed (Figure 13–8). A modified version of a leaf-bud cutting, referred to as a single node cutting, can be prepared simply by cutting the stem below and above the leaf petiole having a well-developed axillary bud. Examples of plants propagated this way include blackberry, camellia, clematis, devil’s ivy, dracaena, grape ivy, heart-leaf philodendron, jade plant, mahonia, rhododendron, and rubber plant.

Cane Cuttings

A cane cutting is an easy way to propagate some overgrown, leggy houseplants such as dumbcane, corn plant, Chinese evergreen, and other plants with thick stems. Leafless stem sections (2 to 3 inches long) are cut from older stems. Each cane should contain one or two nodes (Figure 13–9). Lay the cutting horizontally on the medium, or insert it vertically with about half of the cutting below the surface of the medium, and leave a bud facing upward. Cane cuttings are usually potted when roots and new shoots appear.

Stem Cuttings

Propagation by stem cuttings is the most commonly used method for many woody ornamental plants. Typically, stem cuttings of tree species are more difficult to root successfully; however, cuttings from trees such as crape myrtles, some elms, and birches can be rooted.

Types of Stem Cuttings

Herbaceous cuttings are made from nonwoody, herbaceous plants such as coleus, chrysanthemums, and dahlia. A 3-inch to 5-inch piece of stem is cut from the parent plant. The leaves on the lower one-third to one-half of the stem are removed, and the cutting is placed in the rooting medium. A high percentage of the cuttings root, and they do so quickly.

Softwood cuttings are prepared from soft, succulent, new growth of woody plants, just as it begins to harden (mature). Shoots are suitable for making softwood cuttings when they can be snapped easily when bent and when they still have a gradation of leaf size (oldest leaves are mature whereas newest leaves are still small). For most woody plants this stage occurs in May, June, or July. The soft shoots are quite tender, and extra care must be taken to keep them from drying out. The extra effort pays off, though, because they root quickly.

Semi-hardwood cuttings are usually prepared from partially mature wood of the current season’s growth, just after a flush of growth. This type of cutting normally is made from mid-July to early fall. The wood is reasonably firm and the leaves of mature size. Many broadleaf evergreen shrubs and some conifers are propagated by this method.

Hardwood cuttings are taken from dormant mature stems in late fall, winter, or early spring. Plants are generally fully dormant with no obvious signs of active growth. The wood is firm and does not bend easily. Hardwood cuttings are most often used for deciduous shrubs but can be used for many evergreens. Examples of plants propagated at the hardwood stage include fig, forsythia, grape, privet, and spirea. The three types of hardwood cuttings are straight, heel, and mallet (Figure 13–10). A straight cutting is the most commonly used stem cutting. For the heel cutting, a small section of older wood is included at the base of the cutting. For the mallet cutting, an entire section of older stem wood is included.

Propagating Ferns by Spores

Place a solid, sterilized brick in a pan, add water to cover the brick, and bake at 250°F for 30 minutes. When the brick is wet throughout, remove it from the water and place a thin layer of moist soil and peat (1:1 by volume) on top of the brick. Dust spores on the medium. Cover with plastic (not touching the spores) and place the brick in a warm place with indirect light. It may take up to a month for the spores to germinate. Keep moist at all times.

A small, heart-shaped structure, about ¹⁄₈-inch across (called a prothallus) develops first from each spore, forming a light green mat. Mist lightly to maintain high surface moisture because sperm must be able to swim to the archegonia (female organ). After about three weeks, fertilization should have occurred.

About two months later, pull the mat apart with tweezers in ¹⁄₄-inch squares and space them ¹⁄₂-inch apart in a flat containing a 2-inch bottom layer of sand, a ¹⁄₄-inch layer of charcoal, and a top 2-inch layer of a mixture of potting soil and peat (1:1 by volume). Cover with plastic and keep moist. When fronds (fern «leaves») appear, transplant to small pots. Reduce humidity gradually until plants can survive in less humid conditions. Light exposure may be increased at this time.

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Procedures for Rooting Woody Stem Cuttings

Cuttings should generally consist of the current or past season’s growth. Avoid material with flower buds. Remove any flowers and flower buds when preparing cuttings so the cuttings’ energy can be used in producing new roots rather than flowers. Take cuttings from healthy, disease-free plants.

The fertility status of the stock (parent) plant can influence rooting. Avoid taking cuttings from plants that show symptoms of nutrient deficiency. Conversely, plants that have been fertilized heavily, particularly with nitrogen, also may not root well. The stock plant should not be under water stress. In general, cuttings taken from young plants root quicker than cuttings taken from older, more mature plants. Cuttings from lateral shoots often root better than cuttings from terminal shoots.

Early morning is the best time to take cuttings because the plant is fully turgid. It is important to keep the cuttings cool and moist until they are stuck. An ice chest or a dark plastic bag with wet paper towels may be used to store cuttings. If there will be a delay in sticking cuttings, store them in a plastic bag in a refrigerator.

While terminal bud ends of the stem are best, a long shoot can be divided into several cuttings. Cuttings are generally 4 to 6 inches long. Use a sharp, thin­bladed pocketknife or sharp pruning shears. Dip the cutting tool in rubbing alcohol or a mixture of one part bleach to nine parts water to prevent transmitting diseases from infected plant parts to healthy ones.

Remove the leaves on the lower one-third to one-half of the cutting (Figure 13–11). On large-leafed plants, the remaining leaves may be cut in half perpendicular to the midvein to reduce moisture loss and conserve space in the rooting area.

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During preparation of stem cuttings of particular woody species, the lower portion of the stem that is inserted into the rooting media is deliberately wounded, which is done to stimulate rooting. Most species do not require wounding, but some benefit greatly from this practice.

Treating cuttings with root-promoting compounds (chemicals), particularly for difficult-to-root species, is a common practice when rooting woody stem cuttings because these compounds increase the percentage of cuttings that form roots, speed up the rooting process (make the cuttings root faster), increase the uniformity of rooting, and lastly increase the number and quality of roots produced per cutting. Root-promoting compounds are generally available commercially in two forms, powders or liquids.

Use a rooting medium such as coarse sand, pine bark, or a mixture of one part peat and one or two parts perlite (by volume), or peat and sand (1:1 by volume). The rooting medium should be sterile, low in fertility, sufficiently well drained to permit aeration, and moisture retentive enough so that it does not have to be watered too frequently. Moisten the medium before inserting cuttings.

Various commercial potting mixes can be used. Insert the cuttings one-third to one-half of their length into the medium with the buds pointing upward. Do not insert the stem upside down. Space cuttings just far enough apart to allow all leaves to receive sunlight. Water again after inserting the cuttings if the containers or frames are 3 or more inches deep. Cover the cuttings with plastic and place in indirect light. Keep the medium moist until the cuttings have rooted. Rooting is improved if the plants are misted on a regular basis.

Rooting time varies with the type of cutting, the species being rooted, and environmental conditions. Conifers require more time than broadleaf plants. Late fall or early winter is a good time to root conifers. Once rooted, conifer cuttings may be left in the rooting structure until spring.

Root Cuttings

Some plants can be propagated from a section of a root. Root cuttings are usually taken from 2- to 3-year-old plants during the dormant season when carbohydrate levels are high. Root cuttings of some species produce new shoots, which then form their own root system, whereas root cuttings of other plants develop root systems before producing new shoots. Examples of plants that can be propagated from root cuttings include blackberry, apple, fig, lilac, phlox, raspberry, rose, sumac, and trumpet vine.

Plants with large diameter roots are normally propagated outdoors. The root cuttings should be 2 to 6 inches long. Make a straight cut on the proximal end (nearest the crown of the parent plant) and a slanted cut on the distal end (farthest from the crown) of each root cutting. Tie the cuttings in bundles with all the same ends together. It is important to maintain the correct polarity of the cuttings. Store about three weeks in moist sawdust, peat moss, or sand at 40°F. Remove from storage. Plant the cuttings distal end pointed down, about 2 to 3 inches apart in well-prepared garden soil. The tops of the cuttings (proximal ends) should be the shallowest part of the planting at 2 to 3 inches below the soil surface.

For plants with small diameter roots, cut the roots into 1-inch to 2-inch sections. Lay the cuttings horizontally on the medium surface in a flat and cover with about ½-inch of soil or sand. Place the flat inside a plastic bag or cover with a pane of glass. Place the flat in the shade and remove the protective cover after new shoots appear.

Figure 13–4. A small flat can be used to start cuttings.

Chris Alberti

 CC BY 2.0

Figure 13–5. Some plants can be propagated from a leaf petiole cutting (left). New plants form at the base of the petiole (right).

Figure 13–6. Sanseviera trifasciata (snake plant) leaves that were cut and placed in rooting medium.

Chris Alberti

 CC BY 2.0

Figure 13–7. Remove the petiole of a plant such as a rex begonia, cut the veins, and then lay the leaf flat on the surface of the media.

Figure 13–8. Many plants can be propagated by leaf-bud cuttings.

Figure 13–9. Numerous houseplants can be propagated by cane cuttings.

Figure 13–10. The three types of hardwood cuttings are straight, heel, and mallet.

Figure 13–11. A stem cutting is prepared for rooting by removing the leaves from the lower one-third to one-half of the cutting; large leaves should be cut in half perpendicular to the midvein.

Conclusion

For some plants, cutting roots is a periodic necessity to enhance their growth. Now that you know what happens if you cut the roots of a plant, you have to apply extra care when handling the root system of any plant and ensure to give your plants maximum support right after every cutting section.

Ensure to study your type of plant before cutting because pruning brings about injuries, and plants that have underground buds or are unhealthy may not survive the process.

Always maintain pruning tools after use to minimize the risk of spreading infection on the injured plant.

Authors

Extension Associate (Consumer Horticulture)

Horticultural Science

Professor

Horticultural Science

Publication date: Jan. 31, 1999

N.C. Cooperative Extension prohibits discrimination and harassment regardless of age, color, disability, family and marital status, gender identity, national origin, political beliefs, race, religion, sex (including pregnancy), sexual orientation and veteran status.

Authors

Extension Associate (Consumer Horticulture)

Horticultural Science

Professor

Horticultural Science

Publication date: Jan. 31, 1999

N.C. Cooperative Extension prohibits discrimination and harassment regardless of age, color, disability, family and marital status, gender identity, national origin, political beliefs, race, religion, sex (including pregnancy), sexual orientation and veteran status.