Rose Care and Fertilization

Fertilization

(Also consult the American Rose Society: Fertilization web site.)

Roses may be the flowers of love and romance, but there's nothing romantic about spindly canes sporting spider mites, beetles and mildew instead of beautiful flowers. Just as romance sometimes needs a little helping along, so do your roses. The bonus in keeping roses watered, fertilized, mulched and pruned is that the resulting healthy plants are less susceptible to pest attack.

There is perhaps less agreement about how, when and with what to feed roses than any other aspect of their care. If there is any recommendation resembling a consensus of opinion, it would be to feed the modern, repeat-bloom rose varieties first in the spring right after pruning. Next, feed when they have developed flower buds, and then again about two months before the first frost in your area. Gardens with fast-draining, sandy soil or those in southern climates are usually fed more frequently.

Use a commercial rose food or a general-purpose fertilizer like 10-10-10 or 5-10-10 for the first two feedings. A formulation like 0-10-10 is best for the last feeding before frost.

Apply the rose food as well as the water-soluble and foliar fertilizers available according to the manufacturer's directions. Dry fertilizers should be scratched into the soil beneath the leaves - but not touching the canes or bud union - and then watered in well.

The older varieties of roses that only bloom once a year should be fertilized one time in early spring. (For more information, see the American Rose Society: Older varieties)

FEEDING AND SPRAYING ROSES IN SOUTH CENTRAL TEXAS

(Also consult the American Rose Society: Spraying web site.)

Your feeding program, like your spraying, should be done regularly. Roses are heavy feeders. To keep them growing vigorously, an organized program should be followed. Water rose bed thoroughly before and after food has been applied.

  • January thru February -- As the weather and ground warm up, around mid to late February, organic fertilizers may be applied. Give each large bush. one to two cups of a mixture of alfalfa meal, cottonseed meal, fish meal and blood meal, scratch in lightly and water in well.

  • March thru May -- The initial feeding should be chemical, either liquid or dry. It is applied when spring pruning is completed. Carl Pool, Green Light, Miracle-Gro, Peters or Rapid-Gro are all good soluble fertilizers. Give each Hybrid Tea or other large bush, one tablespoon of fertilizer dissolved in a gallon of water.

    For miniatures use one teaspoon of liquid food per gallon of water. Give each plant about a quart. Dry rose fertilizer can be applied in place of liquid. Use according to directions. Liquid feeding in this period should be once a month. Mature climbers should be given double the amount given to Hybrid Teas.

  • June thru August -- With the introduction of timed release fertilizers, a summer long feeding in one application is possible. These fertilizers are formulated to feed continuously for three to six months in our climate. Feed each average sized bush at least three or four ounces, working it lightly into the soil. Water thoroughly. If you don't care to use this type of product, continue feeding with a water soluble food (twice a month), or a monthly application of dry food. As the weather becomes hot, you may want to switch to soluble fertilizers as they are more readily available to the plants. Iron chlorosis occurs at this time; Sprint 330 can correct this deficiency.

  • September thru October -- With the advent of cooler weather and rain, your roses will begin their heavy fall blooming season. Once you have done your light fall pruning, you can apply a cup of organic rose food per bush and follow this two weeks later with a liquid feeding. Don't feed with either liquid or dry foods after the beginning of October.

  • After heavy rains, it is a good idea to give your bushes a supplemental liquid feeding.
With regard to spraying, prevention is critical in keeping your roses free of fungus and insect problems. A hit and miss program will get you and your roses into trouble. Basic spraying can be divided into three different phases.
  • March thru May -- Once bushes have been pruned, a clean up spray consisting of Ortho Funginex and Malathion should be applied to both the bush and the ground area around the bush. This will take care of any over wintering fungus or insect problems. Once your new growth starts, spray every seven days with Funginex, a liquid product. This fungicide has three advantages over others in that it leaves no residue, protects against mildew, blackspot and rust and needs no sticker spreader. Rust is not a big problem in this area, but does appear on occasion. Spray top and bottom of the leaves until the foliage glistens to obtain complete coverage. If your bushes should become infected with either mildew or blackspot, spray every five days until control is obtained. Insecticides such as Diazinon or Orthene can be used about every 14 days to combat most insect problems that occur during this period. Use according to label directions.

  • June thru August - By this time of the year, if our weather is normally (hot and dry), you can lengthen your spraying interval for fungus problems to every 10 to 14 days. Insecticides should be used sparingly. The biggest problem that may occur at this time is an infestation of spider mites. A good way to treat this problem is to apply a hard spray of water to the bottom of the foliage every three or four days throughout the summer. This will interrupt the mites' breeding cycle. (The bushes will also benefit from the washing). A miticide such as Green Light Red Spider Spray may also be used.

  • September thru November - Once the weather begins to cool off and the early morning and nights become more humid, follow the same spray program used during the spring for both fungus and insect problems. To prevent spray bum of foliage in all seasons, water rose beds thoroughly before spraying. in hot weather, spray in early morning or late evening when temperatures are cooler.
When spraying, it is very important to wear protective clothing; this should include a chemical spray mask, gloves and a long sleeved garment.

Mulch

Using mulch, especially an organic one, is about the closest thing possible to a garden panacea. A mulch keeps weeds to a minimum, the soil moist and loose and adds nutrients.

Apply mulch in the spring just as the soil warms and before weeds start coming up. Mulch can also be applied anytime during the growing season if the weeds are removed and the surface lightly cultivated. Spread 2 to 4 inches of mulch over the bed, leaving some space open around the base of each rose. Replace the mulch as it deteriorates during the year.

For organic mulches, you'll want to use whatever is locally available and cheap. Some options include wood chips and shavings, shredded bark, pine needles, or chopped oak leaves. Extra nitrogen fertilizer may be needed when these mulches are first applied. Mixtures of materials are usually more satisfactory as they have less tendency to pack down and, moreover, permit easy transmission of water and fertilizers. Many compost mixtures are available -- also a light layer of manure may be applied under the mulch.

Watering

Adequate soil moisture is indispensable to the vitality of roses. (For more information, see the American Rose Society: Watering) Seldom can you rely on the natural rainfall to be adequate. The rule-of-thumb is 1 inch of water each week, but the actual frequency of watering will depend on your soil and climate as well as the age of the plant.

The goal is to slowly water until the soil is soaked 12 to 18 inches deep. Soaker hoses or a hose with a bubbler attachment are inexpensive solutions and keep water from splashing onto foliage and spreading diseases. Soil-level and drip-irrigation systems are more expensive but make watering a breeze.

Pruning

(For more information, see American Rose Society: Pruning). Pruning controls the size and shape of roses and keeps the modern varieties blooming repeatedly all summer long, as they flower on new growth. The supplies you'll need include a good, sharp, curved-edge pruning shears; long-handled lopping shears; a small pruning saw; plus a pair of leather gardening gloves.

Well-established varieties of modern rose bushes such as hybrid teas, floribundas, and grandifloras should receive a major pruning each spring after the winter protection has been removed and just as the buds begin to swell (usually about when daffodils bloom). Harsh pruning makes bigger, but fewer blooms. And, there is no report that anyone ever killed a plant with a pair of pruning shears.

All that's needed otherwise during the growing season is to remove and destroy any diseased foliage or canes and to dead head, or remove the faded flowers, cutting their stems just above the first leaf with five leaflets.

Most old-fashioned and species roses as well as the climbers that bloom only once a year flower on wood from the previous year's growth. They are pruned right after flowering.

Practically all rose plants are budded on a special root, or understock. Occasionally you may find a sucker, or shoot, growing from this root stock itself. These sucker canes can usually be identified by the different leaf size and coloring. Remove sucker growth by cutting the canes off as close to the root stock trunk as possible.