Q. What are some ways to propagate house plants?
A wide variety of house plants can be propagated relatively easily, In this way you can save your favorite plant once it is past its prime, increase the number of plants in your house or make a plant donation to a friend. No special equipment is required, although if you are going to get into propagation seriously then a covered propagation tray (preferably heated) is useful. The exact method of propagation will depend partly on the species of the plant. Here is a summary of the main methods:
This the most common method used to propagate house plants. There are two different procedures:
- Stem cuttings
There are two different kinds of stem cuttings - soft-wood cuttings and hard-wood cuttings. Take soft-wood cuttings in spring or early summer when the plant is growing rapidly. Cut off a portion of the end of a branch that has several leaves or buds. Remove the lower leaves from the cutting and insert the lower third or so into rooting medium in a tray. The buried tip may be dipped in a rooting hormone preparation to encourage new roots but this is often not necessary. Sprinkle water carefully over the tray and cover with a plastic cover. Place the tray in a warm, bright location away from direct sun.
Hard-wood cuttings are often used for shrubby plants. They may be taken from sections of long stems or shorter side stems. They are trimmed and treated exactly as soft-wood cuttings. Rooting may take anywhere from 10 to 30 days with hard-wood cuttings taking longer than soft-wood cuttings. New leaves and growth will appear when new roots have been established. At this time, transfer the cuttings singly to small pots with one part of sand and one part of peat moss.
- Leaf cuttings
This method is particularly suitable for soft-leaved plants such as African violets (Saintpaulia), begonias, Streptocarpus and Dieffenbachia (dumb canes) and Peperomia. For small leaves, insert about half the leaf into the propagation medium at a slight angle. Treat as described above for stem cuttings. Larger leaves can be cut into pieces before inserting in the medium. Large begonia leaves can also be treated by nicking the veins of the leaves in several places and then laying the leaf (top surface up) on the surface of the potting soil. Plantlets will arise from the nicks
Plants with flexible stems can be propagated by layering. First fill some small pots with potting soil, Then take one of the plant shoots and bend it into a U shape, remove any leaves in the U part and make a small nick at the base of the U. Bury the U part in the soil in the pot and anchor it it with a hair pin. Keep the soil moist and rooting will take place over the next several months.
When this has occurred the new plant can be severed from the parent plant and moved to a larger pot. Spider plants (Chlorophytum comosum) and a few other species make this method easy for you by producing plantlets at the ends of flower stalks. These can be cut off and planted directly in small pots.
Many house plants have crowns or daughter rosettes. This group includes many ferns, Chlorophytum (Spider plant), Maranta and African violets. Remove the plant from the pot and simply divide it into small pieces, using a knife if necessary, The separate parts can then be potted into smaller pots.
House plants are usually not propagated from seeds although it is quite feasible to do so. Seeds vary greatly in size and this partly determines how then are sown. Sowing seeds is best done in shallow, flat trays filled with seed or rooting mixture (not standard potting mixture). For fine seeds, a pinch rubbed between the fingers to disperse them evenly is sufficient. Do not bury the seeds but spray the surface lightly with water. Larger seeds can be buried slightly about 1/4 to 1 inch apart (depending on the size of the seeds). (Knowledge of the requirements of the specific plant is helpful as some seeds need soaking, scoring , heat or cold before they become viable for propagation.) The seeds and developing seedlings should not be allowed to dry out but should be lightly sprayed regularly. Keep the seed tray in a warm location in bright light (but not direct sunlight). Seedlings should be thinned out if they are too crowded and transferred to a pot with regular potting mixture when they have developed a few true leaves.
The following book is a good source of reference on growing house plants, including propagation (pp. 434-445): Reader's Digest Success with House Plants. The Reader's Digest Association, Inc., Pleasantville, NY. (1979)