By Glenn DiNella
Pests in the rose garden can range from minor nuisances to major disasters. While we Southerners love our roses, we spend countless hours and dollars annually on pest and disease control for these precious plants. Since most busy homeowners are looking for low-maintenance garden plants, relatively carefree shrub roses, such as the Flower Carpet Pink Supremes, above, are gaining popularity over the fussier tea roses.
Aphids are a perennial problem for roses. These tiny creatures suck the juices out of the leaves and flower petals, and disfigure the plant. Wasps can be annoying (if you look closely, you’ll see one on the Flower Carpet Pink Supremes above), but keep in mind they eat aphids and other soft-bodied plant pests. So if they are on your roses, just let them enjoy their meal. The same goes for ladybugs.
This method of trying the most environmentally friendly methods first and stepping up to harsher chemicals is the essence of “integrated pest management.” A strong blast from the hose might fix a minor aphid infestation. If not, try a tablespoon of lemon dish soap in a gallon of water, and spray it on the plants. Be sure to spray the undersides of leaves, where these pests usually reside. The acidity of the citrus oil in lemon soap makes it more effective than other soaps.
If you still have pest problems, move up to bigger guns by dusting with a relatively safe chemical such as Sevin. Don’t dust the flowers where bees search for nectar. You can sprinkle granular insecticides around the root zone of a plant and water them in. Plants take up the chemical through their roots and into all parts. This can be a good solution because it kills only the pests dining on the plants’ foliage or flowers.
Rose rosette disease is a frightening new problem for rose enthusiasts. Although some types of roses seem resistant, most types are susceptible. A tiny mite spreads a virus that causes this disease. The mite can travel on the wind or on contaminated pruners or other equipment.
Symptoms of rose rosette disease include a “witch’s broom” of many soft, stunted shoots all over the plant. Also, the leaves crinkle and turn shades of red, and the canes develop an abnormally large number of thorns. There doesn’t seem to be any cure for this disease. The best hope at control is get rid of the plant—carefully.
Here’s how: Tie a string around the base of the plant and wrap the string around the plant several times to confine it.
Place a garbage bag over the plant. The thorns can tear holes in your bag, so you might want to double-bag it. This helps contain any mites.
Cut the plant at ground level, and move it aside.
Dig up as much of the root system as you can, add it to the bag, and tie the bag tightly. Get rid of the bag in the trash, and wash your equipment with bleach water when you are done.
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