IN THE GARDEN THE SWEET SMELL OF ROSE-GROWING SUCCESS.

Byline: JOSHUA SISKIN

Q: Could you please provide a feeding schedule for roses for a whole year? That would make it easier for me to remember when I need to fertilize.

-- G. Bayes, Simi Valley 

A: The question of when and how much to fertilize roses really hinges on your expectations. Roses that are never fertilized, for example, will still flower every spring and will probably flower at least once more, if not twice more, during the growing season as long as their faded flowers are removed prior to formation of hips (rose fruits).

Hip action

Growth of seeds within the hips steals away energy that would otherwise be used for additional flower production.

There are many reports of old rose bushes discovered growing in abandoned cemeteries. These bushes are never fertilized but still manage to put out a respectable crop of flowers each year.

Roses produce their own food or energy supply, which is sugar. Plants manufacture sugar by combining carbon, which is taken from carbon dioxide in the air, with the hydrogen and oxygen that constitute water. Carbon, in the form of carbon dioxide, enters plants through leaf pores or stomata, while water is absorbed from the soil via roots.

Some rose growers increase the concentration of carbon dioxide in their greenhouses in order to increase flower production. In Finland, rose bushes flower year-round in greenhouse air enriched with carbon dioxide. Similarly, in Holland, carbon dioxide emissions from oil refineries are pumped into rose growers' greenhouses -- with positive results.

Two kinds of fertilizer

There are both inorganic and organic fertilizers and each has its own application schedule.

Inorganic fertilizers need to be applied more frequently, as they break down quickly in warm weather. Hybrid tea and Flower Carpet roses are the heaviest feeders, and you will want to apply 1/2 to 1 cup of a rose-specific fertilizer to each plant during the first week of every month from April through August. You can make another application after leaves have fallen, or been picked off to induce dormancy following pruning, in late December before winter rains begin.

Floribundas, of which `Iceberg' and `Simplicity' are the most popular cultivars, can be fertilized half as much as hybrid teas.

If you prefer to fertilize organically, your application frequency will be significantly reduced according to the experience of Mark Whitelaw, a Texas rosarian. His recommendation is to fertilize twice a year, in February and August, with one cup of the following mixture per plant: 8 parts alfalfa meal, 2 parts cottonseed meal, 2 parts rock phosphate, 2 parts bone meal, 1 part blood meal and 1 part Epsom salts.

Whitelaw stands by this fertilization regime for azaleas and all other flowering perennials as well. You can find these and other organic products at nurseries, feed stores and over the Internet at www.groworganic.com.

TIP OF THE WEEK: Late summer and early fall are propitious times for propagating your favorite roses from cuttings. Dip the bottom third of rose cuttings (4 to 6 inches in length) in hormone powder.

As recommended by rosarian Whitelaw, dip hormone-treated cuttings in a solution of 1 teaspoon SUPERthrive (a root stimulant) per gallon of water. Then place cuttings in small pots filled with any well-drained potting mix and situate them in bright shade, such as that provided beneath a tall tree. Hormone powder and SUPERthrive are available at most nurseries.