Plants for Profit

How To Increase Your Plant Supply

As the owner of a small greenhouse, you will find it more profitable to buy rooted cuttings of foliage plants, geraniums, hoya (wax plant), hydrangeas, and many others than to give over space to propagating them. But in the case of rare plants, such as hybrids you have developed or collector's varieties of African violets or gloxinias, you will want to grow your own stock. With African violets you need not wait for good-sized plants to develop from cuttings; zealous collectors will buy rooted or un-rooted leaf cuttings taken from choice plants.

A propagating case made of plastic, an ordinary flat with a glass or plastic covering, or a flat of soil with a heating cable installed in it will speed rooting of all kinds of cuttings and hasten seed germination too. Sphagnum moss, sand, and vermiculite are ideal for rooting cuttings. As they contain no nutrients, material rooted in them should be shifted as soon as possible to regular growing soil. If you cannot shift plants right away, feed them with a weak solution of liquid fertilizer, to prevent spindly growth.

How to Take Cuttings

Use a sharp knife to take a cutting. There are two kinds— stem and leaf. Most plants, geraniums, coleus, fuchsias, and wax begonias, form new roots more rapidly when the stem cutting is taken about 1/4 to 1/2 inch below a node (the leaf-stem joint). Two or more top leaves are left on but the lower ones are stripped off, and all flower buds are removed.

Stem cuttings of cacti, geraniums, and poinsettias should be allowed to dry in the air for at least 24 hours before planting. In fact, some cacti specialists let the cuttings dry for 4 to 6 days before planting. With plants that have juice-filled stems, this drying time forestalls possible rot.

Leaf Cuttings

African violets, gloxinias, and other gesneriads, rex begonias, peperomia, hoya, echeveria, and sedums are among the many plants you can propagate from single leaves.

Cut the leaf off with about ½ inch of petiole (leaf stem) and insert it in sand, sphagnum moss, vermiculite, or a mixture of all three, right up to the edge of the leaf blade. If you are using a heating coil for faster propagating, keep the soil temperature about 75 degrees and the air temperature 70 degrees.

You can transplant the cuttings to 2-inch pots after 2 or 3 weeks, or you can leave them in the propagating case until they show new plants—usually in about a month and then transplant them.

If you have some especially nice geraniums you want to increase, try propagating them through the leaf-bud system. In each leaf axil (the point where leaf stem joins plant stem), there appears a small bud of new growth. Make your leaf cutting so this growth bud remains attached and propagate as you would single leaf cuttings. With this method you will get many more cuttings per plant than if you had taken regular slips. These cuttings root within 10 days. 

Azaleas,  bougainvillea, chrysanthemum,   and  croton  are   some  others  to  propagate through the leaf-bud method.

With rare varieties of rex begonia or gloxinia, you can multi­ply your stock by another leaf-cutting method. Take a leaf and slice through the large veins in several places. Insert the cut veined leaf in a propagating case, in moist sand, and little plants will form at each of the cuts.

Air-Layering

If you want to produce more plants from an aged and un­gainly rubber plant or dieffenbachia, make a slit in the stem just below some shapely top growth. Moisten a handful of sphagnum moss and place it around the slit stem; then wrap with polyethylene plastic. Secure the plastic and moss packing, top and bottom with rubber bands or with the covered-wire Twist-Ems.   Keep   the   moss  moist - which is not  much of a job since the plastic blocks the passage of water vapor while permitting the passage of air. Indeed, you may not have to water but once during the usual 6-week rooting period. When the ball of moss is filled with roots, cut the stem below roots and put the "new" plant in good greenhouse soil.

You can keep the old plant too, for it probably will sprout new foliage. This type of propagation is called air-layering. Soil layering is based on the same principles; but in this method, stems are bent down to the soil and rooted there.