AUBURN UNIVERSITY, Ala. – Fall is a good season in Alabama for rose plant growth and flowering. It is an excellent time to rejuvenate roses for a beautiful show of color before they rest for the winter. With adequate watering, some fertilization and clean up, gardeners will enjoy many weeks of colorful blooms in the fall.
To rejuvenate a rose plant and allow it to form new growth, growers should prune any dead, diseased canes as well as spent blooms. The amount and type of pruning needed depends on the variety. No need to prune as heavily in the fall as in the spring.
Mallory Kelley, an Alabama Extension agent of home horticulture, said timing is key when pruning roses.
“If you prune too late in the fall you would not have time to get more blooms and tender growth could be susceptible to frost damage,” Kelley said.
The tender, new growth that roses put on after pruning will most likely require protection from sucking pests such as aphids, thrips and beetles. Insecticidal soap is your first line of defense against these pests. A pyrethrin insecticide, is a contact killer and must be applied to the pest. Products that contain active ingredients such as Carbaryl or Malathion work as nerve poisons and feeding by any insect with result in death.
Kelly says she would not use trade names. She would use active ingredients such as Orthene or Sevin to control adult beetles.
Mulch Is Key To Growing Roses
Mulch is key to growing roses successfully in the South. Kelley recommends waiting until winter to replace mulch around rose plants.
Replace with 3 to 4 inches of clean pine straw. If you don’t have enough pine straw, use leaves shed from shade trees topped off with an inch or so of pine straw. The leaves will decay over time, adding hummus to the soil.
Roses respond well to cooler nights and less humid days if growers provide adequate moisture and one last application of fertilizer in early fall. If growers used a fertilizer such as 10-10-10 during the spring or summer months, only a small amount of nitrogen is needed.
“You don’t want put too much nitrogen on late in the year,” Kelley said.
One-half pound of ammonium nitrate (34-0-0) broadcast per 100 square feet of bed should be sufficient.
Instead of having to wash fertilizer off of the leaves, use a water-soluble fertilizer. Fertilize roses about every two to three weeks until six weeks before the first expected killing frost. This will allow the plant time to begin their dormancy period before freezing weather arrives.
Find more information about planting and growing roses in the Alabama Extension publication Growing Roses. Also, you can contact your county Extension office with any other questions.