Shrubs that can be propagated by cuttings allow the avid or beginning gardener an easy way to add more plants to the landscape without spending a lot of money. Through bottom heat and the use of a rooting compound, making new plants from 4- to 6-inch shrub cuttings is easy.
The best time to take the cuttings from the shrubs is either in the early spring or late fall. Early spring provides soft wood from new growth which roots quickly. The late fall cuttings are referred to as hardwood cuttings and can take up to two months to root properly for planting.
Flowering shrubs, like flowering quince and viburnum, can be propagated by cutting 4 to 6 inches of spring growth from the original plant. Other shrubs easily propagated by cuttings include honeysuckle and azalea.
It is important only to allow the top two leaves to remain on the shrub cuttings for photosynthesis to take place. Once the bottom leaves of the cuttings are removed, dip the cuttings into a rooting hormone and place the section of shrub into a growing pot filled with moist potting soil. Cover the growing pot with clear plastic and place in a warm place out of direct sunlight. In a few weeks, roots will form on the cuttings. It is necessary to allow the new plant to grow in the pot until the weather is conducive to planting outdoors.
Spirea, with its tiny white blooms, grows well from soft wood cuttings. Lilacs and weigela also provide excellent cuttings for propagation.
Evergreen shrubs must be propagated in late fall or early winter for good results. The cuttings are considered hardwood and need treated with a rooting compound before placing them into growing trays. Apply bottom heat and avoid direct sunlight. Acceptable bottom heat temperature is 75 to 80 degrees. Keep the soil damp but not wet.
Evergreen shrubs such as thuja and boxwood root easily and grow quickly once the roots form. Other shrubs for the landscape which can be propagated by cuttings include holly and juniper. These slow growing evergreens take longer to grow a healthy root system but are well worth the effort.
Care of Cuttings
Early spring provides the best time to take cuttings from flowering shrubs and also allows gardeners to add the new plants to the flower bed or landscape the same year. As long as the new plants, grown from cuttings, have been hardened off and remain healthy during the growing season, the only extra precaution needed is a good layer of mulch during the first winter. By the second growing season, the new plants are able to be treated as any other plant in the landscape.
Due to the late time frame for evergreen shrub cuttings, a year of potted growth aids in healthier plants. Once the cutting has a healthy root system, pot the new plant in a planter and keep on the patio or other sheltered area until the following growing season. This ensures the plant grows without any damage from the outside elements until the root system is fully developed and provides adequate nutrients to the young plant.