ROSES IN THE FALL
by Jerry Parsons, Ph.D.
Horticulture Specialist, Texas Agricultural Extension Service in San Antonio

"A rose by any other name is just as sweet". But would it create the same joy and excitement? People like roses. And would-be rose growers purchase thousands of bushes annually, anticipating the beauty they are famous for producing.

In Texas, where everything is bigger and better, rose growing is no exception. Rose blooms may last longer in cooler climates, but cooler climates do not afford the potential for 2 spectacular bloom seasons as Texas does each year. Most of us expect our roses to bloom well in the spring, but we overlook the best possible rose season--fall.

Hot weather greatly reduce the life-span and beauty of rose blooms. During the spring rose-bloom season, Texas weather is making the transition from winter to summer. Unfortunately, the transition period may only last several days. Texas temperatures rapidly change from frosty to scorching.

In comparison, fall is ideal for rose blooms. Usually, our extremely hot weather ends in September and cooler temperatures, especially at night, signal that the "second spring" of South Central Texas has begun. These cooler temperatures stimulate rose bush growth and intensify the color of the rose blooms. Many people do not prepare their roses for this second spring, so they miss the most spectacular, longest-lasting bloom period.

September is the time to act. Roses should be pruned or groomed during the first 2 weeks in September--no later than September 20. Fall pruning is lighter than in the spring. Cut about 1/4 - 1/3 of the bush.

When pruning miniatures, other than cleaning them out, simply cut off all the blooms. When pruning standard size roses, remove all the blooms and bloom pods. When removing the recommended 1/4 of the bush, cut all canes back to the pencil-sized wood, if the variety permits; and remove any crossing canes which might rub and damage adjoining ones. Also remove any dead or diseased wood. The general shape of a rose bush should be open-centered or vase-like, with canes evenly distributed around the outside. To prolong the bloom period, you may want to prune only 1/2 of your rose bush at a time, then wait a week to complete the process. The half that was pruned first will bloom first, about 45 days after pruning occurred. Remember to complete all fall pruning no later than September 20.

The peak rose bloom season should begin in mid-October. Remove and dispose of all diseased leaves with black spots on the foliage. Black spot and powdery mildew fungus must be prevented rather than cured. Black spot and powdery mildew are fungus diseases. Prevention is easily accomplished by using Funginex fungicide on a 7-10 day spray schedule. Orthene insecticide may be added for control of thrips (thrips cause blooms to stay closed or be misshapen). By September, the spray interval should be shortened to every 7 days since disease is more prevalent. Spraying should continue until the first hard freeze occurs.

After fall pruning has been completed, give the bushes a "shot in the arm" with the addition of fertilizer. Feeding with a water- soluble fertilizer should occur every 2 weeks. Follow instructions by mixing 1 tablespoon of water soluble fertilizer per gallon of water. Pour a gallon of solution around each plant. Don't feed with either liquid or dry fertilizers after October 15th so that growth can slow and harden for the winter cold.

Roses need water. Proper watering causes bushes to develop into larger plants, which produce a much greater volume and quality of blooms. Water can be efficiently applied with soaker hoses, drip irrigation, or specially designed automatic sprinkling devices. Keep in mind that most rose varieties are less disease-prone if their foliage remains dry. Deep watering at weekly intervals is far superior to frequent light sprinkling.

Mulches can help conserve water while moderating soil temperatures during extremely hot weather. The application of bark, pine needles, peat moss, or shredded oak leaves several inches deep to beds or individual plants is an excellent practice. The mulch can be supplemented with 2 inches of horse manure in December, which adds organic materials as well as some fertility to the soil.

Once you begin to produce these beautiful fall roses it is important that they be cut properly to insure bloom longevity. Improper cutting of flowers can injure the plant and decrease its vigor. It is best to cut few, if any, flowers during the first blooming season of a plant. By removing only the flowers and not the stem, the plants will develop into larger bushes by fall, at which time some flowers may be cut. Early removal of foliage and long stems reduces the food manufacturing capacity of the plant and subsequent flower yield.

When you cut roses, be sure to use sharp tools and allow at least 2 leaves to remain between the cut and the main stem. Use sharp shears just above the topmost leaf. Roses that are cut just before the petals begin to unfold will open normally and remain in good condition longer. Late afternoon is the best time of day to cut roses. Always cut bloom stems back to pencil-sized wood, or where 5-leaflet leaves occur. Beginning in mid-November, leave old blooms and pods on the stems to force plants into dormancy. This winterizing will enable better plant survival in the winter.

Plunge the stems immediately into warm water (about 100 degrees F.) and cut the stems again, just an inch or so from the base. Add flower preservatives to the water, according to label instructions, if maximum life is desired. Research has shown that flower preservatives can be helpful in prolonging the beauty of cut flowers. Such preservatives can be purchased from retail florists or from the floral departments in most supermarkets. A mixture of 7-Up soda water (but not the diet type) mixed equally with water has also been shown to be an effective preservative. It is important for the mixture to stand long enough for most of the air bubbles to dissipate.

Good, pure water is equally important as using preservatives. Rain water or distilled water should be used when arranging flowers, since sodium and other materials in most tap water can shorten their life.

Place the flowers in a cool, draft free area until ready to use. High temperatures and direct sun quickly take their toll on cut flowers.

So, take action now to insure that you don't miss our second spring and the beauty of the roses that can adorn it. If you want more information on growing roses locally, see:

http://aggie-horticulture.tamu.edu/plantanswers/publications/roses/rose.html