Erv Evans, Extension Associate
Frank A. Blazich, Professor
Department of Horticultural Science

Propagation by stem cuttings is the most commonly used method to propagate many woody ornamental plants. Stem cuttings of many favorite shrubs are quite easy to root. Typically, stem cuttings of tree species are more difficult to root. However, cuttings from trees such as crape myrtles, some elms, and birches can be rooted.

A greenhouse is not necessary for successful propagation by stem cuttings; however, maintaining high humidity around the cutting is critical. If rooting only a few cuttings, you can use a flower pot (Figure 1). Maintain high humidity by covering the pot with a bottomless milk jug or by placing the pot into a clear plastic bag. Cuttings can also be placed in plastic trays covered with clear plastic stretched over a wire frame (Figure 2). Trays must have holes in the bottoms for drainage. The plastic will help keep the humidity high and reduce water loss from the cuttings.

Figure 1.	Figure 2.

If you need more elaborate facilities, you can construct a small hoop frame and/or use an intermittent mist system. Horticulture Information Leaflets 404 and 405 describe how this can be accomplished. Another bulletin that may be helpful is AG-426 (A Small Backyard Greenhouse for the Home Gardener).

Types of Stem Cuttings

The four main types of stem cuttings are herbaceous, softwood, semi-hardwood, and hardwood. These terms reflect the growth stage of the stock plant, which is one of the most important factors influencing whether or not cuttings will root. Calendar dates are useful only as guidelines. Refer to Table 1 for more information on the best time to root stem cuttings of particular ornamental plants.

Table 1. Optimum stage of tissue (wood) maturity for rooting stem cuttings of selected woody ornamentals

Evergreen Plants

Common Name	Scientific Name	Type of Cutting
Abelia	Abelia spp.	SH, HW
Arborvitae, American	Thuja occidentalis	SH, HW
Arborvitae, Oriental	Platycladus orientalis	SW
Azalea (evergreen & semi-evergreen)	Rhododendron spp.	SH
Barberry, Mentor	Berberis x mentorensis	SH
Barberry, Japanese	Berberis thunbergii	SH, HW
Barberry, Wintergreen	Berberis julianae	SH
Boxwood, Littleleaf	Buxus microphylla	SH, HW
Boxwood, Common	Buxus sempervirens	SH, HW
Camellia	Camellia spp.	SW, SH, HW
Ceanothus	Ceanothus spp.	SW, SH, HW
Cedar	Cedrus spp.	SH, HW
Chamaecyparis; False Cypress	Chamaecyparis spp.	SH, HW
Cotoneaster	Cotoneaster spp.	SW, SH
Cryptomeria, Japanese	Cryptomeria japonica	SH
Daphne	Daphne spp.	SH
Eleagnus, Thorny	Elaeagnus pungens	SH
English ivy	Hedera helix	SH, HW
Euonymus	Euonymus spp.	SH
Fir	Abies spp.	SW, HW
Gardenia; Cape jasmine	Gardenia jasminoides	SW, SH
Heath	Erica spp.	SW, HW
Hemlock	Tsuga spp.	SW, SH, HW
Holly, Chinese	Ilex cornuta	SH, HW
Holly, Foster's	Ilex x attenuata 'Fosteri'	SH
Holly, American	Ilex opaca	SH
Holly, Yaupon	Ilex vomitoria	SH
Holly, English	Ilex aquifolium	SH
Holly, Japanese	Ilex crenata	SH, HW
Jasmine	Jasminum spp.	SH
Juniper, Creeping	Juniperus horizontalis	SH, HW
Juniper, Chinese	Juniperus chinensis	SH, HW
Juniper, Shore	Juniperus conferta	SH, HW
Leyland cypress	x Cupressocyparis leylandii	SH, HW
Magnolia	Mahonia spp.	SH
Oleander	Nerium oleander	SH
Osmanthus, Holly	Osmanthus heterophyllus	SH, HW
Photinia	Photinia spp.	SH, HW
Pine, Mugo	Pinus mugo	SH
Pine, Eastern white	Pinus strobus	HW
Pittosporum	Pittosporum spp.	SH
Podocarpus	Podocarpus spp.	SH
Privet	Ligustrunum spp.	SW, SH, HW
Pyracantha; Firethorn	Pyracantha spp.	SH
Rhododendron	Rhododendron spp.	SH, HW
Spruce	Picea spp.	SW, HW
Viburnum	Viburnum spp.	SW, HW
Yew	Taxus spp.	SH, HW

SW = softwood, SH = semi-hardwood, HW = hardwood

Deciduous Trees

Common Name	Scientific Name	Type of Cutting
Azalea (deciduous)	Rhododendron spp.	SW
Basswood; American linden	Tilia americana	SW
Birch	Betula spp.	SW
Bittersweet	Celastrus spp.	SW, SH, HW
Blueberry	Vaccinium spp.	SW, HW
Broom	Cytisus spp.	SW, HW
Callery pear	Pyrus calleryana	SH
Catalpa	Catalpa spp.	SW
Clematis	Clematis spp.	SW, SH
Crabapple	Malus spp.	SW, SH
Crape myrtle	Lagerstroemia indica	SH
Cherry, Flowering	Prunus spp.	SW, SH
Dawn redwood	Metasequoia glyptostroboides	SW, SH
Deutzia	Deutzia spp.	SW, HW
Dogwood	Cornus spp.	SW, SH
Elderberry	Sambucus spp.	SW
Elm	Ulmus spp.	SW
Euonymus	Euonymus spp.	HW
Forsythia	Forsythia spp.	SW, SH, HW
Fringe tree	Chioanthus spp.	SW
Ginkgo, Maidenhair tree	Ginkgo biloba	SW
Goldenrain tree	Koelreuteria spp.	SW
Hibiscus, Chinese	Hibiscus rosa-sinensis	SW, SH
Honey locust	Gleditsia triacanthos	HW
Honeysuckle	Lonicera spp.	SW, HW
Hydrangea	Hydrangea spp.	SW, HW
Ivy, Boston	Parthenocissus tricuspidata	SW, HW
Larch	Larix spp.	SW
Lilac	Syringa spp.	SW
Maple	Acer spp.	SW, SH
Mock orange	Philadelphus spp.	SW, HW
Mulberry	Morus spp.	SW
Poplar, Aspen; Cottonwood	Populus spp.	SW, HW
Poplar, Yellow; Tulip tree; Tulip poplar	Liriodendron tulipifera	SH
Quince, Flowering	Chaenomeles spp.	Sh
Redbud	Cercis spp.	SW
Rose of Sharon; Shrub-althea	HIbiscus syriacus	SW, HW
Rose	Rosa spp.	SW, SH, HW
Russian olive	Elaeagnus angustifolia	HW
Serviceberry	Amelanchier spp.	SW
Smoke tree	Cotinus coggygria	SW
Spirea	Spiraea spp.	SW
St. Johnswort	Hypericum spp.	SW
Sumac	Rhus spp.	SW
Sweet gum	Liquidambar styraciflua	SW
Trumpet creeper	Campsis spp.	SW, SH, HW
Virginia creeper	Parthenocissus quinquefolia	SW, HW
Weigela	Weigela spp.	SW, HW
Willow	Salix spp.	SW, SH, HW
Wisteria	Wisteria spp.	SW

SW = softwood, SH = semi-hardwood, HW = hardwood

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.

Procedures for Rooting Stem Cuttings

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.

Figure 4.

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.

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.