Growing Plants from Cuttings
This technique works for the majority of plants and produces exact replicas of the donor. Unlike divisions or layers, cuttings are dependent on your care and a supportive environment until they are self-sufficient. Some are quicker to root than others, and different types will be more successful if taken at a particular time of year.
Types of Cutting
Cuttings can be taken from both stems and roots:
- Stem or shoot cuttings are distinguished by the age and maturity of the shoots used.
- Root cuttings are sections of root, normally taken from the parent plant when it is dormant in winter. The downside is that the parent plant will need to be dug up.
Stem cuttings also differ according to when they are taken:
- Hardwood cuttings are taken from mid-fall onward, when shoots are woody and the leaves have fallen. Although the slowest of the stem cuttings to root, most are simple and can be grown outdoors.
- Softwood cuttings root quickly and are best taken in spring and summer, using the soft, new tips of the current year’s young shoots before they start to become woody.
- Semiripe cuttings are taken from early summer to early fall, when the bases of the shoots are firm, or “ripe,” but the tips are still soft and green. Because the cuttings are firmer, they are often easier to deal with than soft cuttings.
You will need both pruners and a knife; clean them before taking each new batch of cuttings and keep them sharp. Use fresh potting mix and new or sterilized containers. Cuttings must be spaced out when planted, so that their leaves do not touch. Small pots, about 31⁄2 in (9 cm) in diameter, are ideal for single cuttings; a 5–6-in (13–15-cm) pot will hold several cuttings. Larger quantities can be rooted in a module or cell tray at least 2 in (5 cm) deep. Use a commercial potting mix that is free-draining, or mix your own from equal parts soilless seed-starting mix or sifted leafmold and sharp horticultural sand or grit.
Natural warmth will often be enough to root cuttings in summer if pots are enclosed in plastic bags or trays are covered with lids. At cooler times, or if you produce lots of plants from cuttings, a propagating case on a heated tray or a heated propagator with a thermostat will remove much uncertainty. Hormone rooting preparations speed root initiation, and usually contain a fungicide; use them sparingly. Buy some each season and store in a refrigerator.