Once you've taken cuttings of old roses from a cemetery, old house or vacant lot, what's the next step? Most roses are easily propagated by rooting cuttings. Here are some tips for success:

Age -- Make sure you take cuttings from firm but young stems. On a repeat-flowering variety, that would be stems on which the flowers are fading or from which the petals have just fallen. On a once-flowering plant, you can use stems from which the flowers are fading in the spring, or similar-age wood from subsequent growth flushes throughout the summer or fall.

Leaves -- Roses root best if the cutting has some leaves still attached, to provide sugars from photosynthesis as well as root-promoting hormones. Some varieties will root from leafless cuttings, but it's better to allow two or three leaves to remain. Keep a spray bottle of water handy to mist over the cuttings while working on them, to keep them crisp, since wilted cuttings often fail to root.

Cuts and "wounding" -- Roses can form roots at any point along the stem, so the exact site of the cut is not important. Many people "wound" the base of the cutting, either by making 1/2- to 1-inch vertical slits through the bark, or by slicing a strip of bark off one or two sides of the base of the cutting with the clipper blade. Difficult varieties often benefit from such wounding, sending out roots all along the wound.

Rooting hormones -- You can root most rose varieties without the use of hormone preparations. This is because rose cuttings contain auxin (indoleacetic acid -- "IAA"), a natural root-promoting hormone. It is produced by the leaves and growing buds or shoot tips and accumulates at the bottom of a cutting, where the roots will form. But some roses apparently don't produce adequate supplies of auxin and are difficult to root. If they produce any roots at all, they are few and weak. So, many growers apply a commercial hormone preparation to stimulate the production of strong roots. These products all contain synthetic auxin, usually indolebutyric acid (IBA) and/or naphthaleneacetic acid (NAA).

Moisture -- One of the most important factors in successfully rooting cuttings is maintaining adequate moisture, both in the soil and in the form of humidity in the air. Place the cuttings in pots of moist sand or potting soil, then cover them with a plastic bag, mayonnaise jar or inverted two-liter soft drink bottle with the top cut off, creating a small tent or "greenhouse" to maintain high humidity around the cuttings.

Light -- Roses root best in bright light. But when using the mini-greenhouse method, it's important to avoid overheating by giving some shade from hot, midday sun. Put the cuttings in bright shade, such as against the north wall of a building or under a tree, to allow rooting without too much heat build-up.

Season -- Most cuttings root best in the spring or early summer, when the weather is warm but not miserably hot. You can root cuttings at other times of the year, but it may take longer and a smaller percentage of them may take. A few types (such as the gallicas) may root more successfully in the autumn.

Timing -- In May or early June, some varieties will have good roots in as little as two weeks. Nearly any variety can be rooted in three to four weeks at that time of year. At other times the process takes longer -- up to seven or eight weeks. There are several ways to tell whether a cutting is rooted. You can tug lightly on it, and if it resists being pulled out of the pot, it likely has roots. Also, roots growing out the drainage holes in the bottom of the pot are a sure indication of success. Cuttings that are actively growing new leaves usually have roots, whereas unrooted cuttings tend not to produce much new top growth.

Once the cuttings are rooted and have been removed from the rooting area, harden them off for a few days by putting the pots in a cool, shady area. Moving them immediately into hot sunshine may damage or even kill the plants. Once they have a good, large root system and are putting out new growth, they can be moved into brighter light.

Dr. Malcolm Manners is Professor of Citrus and Environmental Horticulture at Florida Southern College, where he manages a collection of more than 400 rose varieties and teaches courses in plant propagation. He is secretary and a trustee of the Heritage Rose Foundation. (Reproduced by permission)

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