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Author: COBB PubID: ANR-0401 |
Title: | DISEASE & INSECT CONTROL FOR ROSES |
Pages: 4
Status: DISCONTINUED |
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| Disease And Insect Control For Roses |
Protecting the foliage from early spring infections is the key to season-long black spot and powdery mildew control. To accomplish this goal, begin fungicide spray programs shortly after budbreak and continue at regular intervals until the first hard frost.
Generally, you should make fungicide applications at 10- to 14-day intervals during dry weather, depending on the fungicide used. During rainy weather, a 5- to 7-day interval between applications may be needed to maintain disease control. See Table 1 for specific spray intervals for recommended fungicides.
| Disease / Chemical | Rate Of Application | Comments | |
| Per Gal. | Per 100 Gal. | ||
| Blackspot | 1 T. 1 T. |
1 lb. 1 lb. |
Apply at budbreak. Repeat at 7- to 14-day intervals until frost. For best results, stay on 7-day spray intervals. Shorten spray intervals during wet weather. Chlorothalonil and folpet may scorch foliage during summer. |
| benomyl BENLATE 50W TERSN 1991 50W | |||
| chlorothalonil BRAVO 4.17F DACONIL 2787 DACONIL 2787 75W DACONIL MULTIPURPOSE FUNGICIDE 29.6F |
2 t. 2 t. 2-1/2 t. 2-1/4 t. |
2 pt. 2 pt. 1-1/2 lb. | |
| folpet PHALTAN 75W FOLPET 50W |
1 T. 1-2 T. |
1-2 lb. | |
| mancozeb DITHANE M-45, 80W FORE 80W |
2 t. 2 t. |
1-1/2 lb. 1-1/2 lb. | |
| triforine FUNGINEX ROSE DISEASE CONTROL 6.5 E TRIFORINE 18.2E |
1 T. | 12-18 fl. oz. | |
| Botrytis Blight | 1/2 T. 1/2 T. |
1/2 lb. 1/2 lb. |
Regular blackspot sprays should control botrytis blight. Shorten spray intervals to 7 days for best protection. Remove blighted blooms and shoots. Problems occur during wet, overcast weather. |
| benomyl BENLATE 50W TERSAN 1991 50W | |||
| chlorothalonil BRAVO 4.17F DACONIL 2787 4.17F DACONIL 2787 75W |
2 t. 2 t. 2-1/2 t. |
2 pt. 2 pt. 1-1/2 lb. | |
| iprodione CHIPCO 26019 50W |
1-2 lb. | ||
| DCNA BOTRAN 75W |
1/2 - 3/4 lb. | ||
| thiophanate-methyl + mancozeb ZYBAN 75W DUOSAN 75W |
2-1/2 t. 2-1/2 t. |
1-1/2 lb. 1-1/2 lb. | |
| Powdery Mildew | 1/2 T. 1/2 T. |
1/2 lb. 1/2 lb. |
Regular blackspot sprays should control powdery mildew. Otherwise,
apply at first sign of disease and repeat at 5- to 14-day intervals. Milban is a RESTRICTED USE pesticide. Rubigan may affect leaf growth during cool, overcast weather. |
| benomyl BENLATE 50W TERSAN 1991 50W | |||
| copper oleate POWDERY MILDEW CONTROL 15S |
1 T. | ||
| dinocap KARATHANE WD 19.5W |
2/3 T. | 6-8 oz. | |
| dodemorph MILBAN 39E |
1 qt. | ||
| fenarimol RUBIGAN A.S. 1.0E |
4-12 fl. oz. | ||
| triadimefon BAYLETON 25W |
1/10-1/5 t. | 2-4 oz. | |
| triforine FUNGINEX ROSE DISEASE CONTROL 6.5E TRIFORINE 18.2E |
1 T. | 1-1/2 pt. 12-18 fl. oz. | |
| Canker | Maintain good plant vigor. Prune out diseased canes. Use dormant spray of lime-sulfur. | ||
| None labeled | |||
| Crown Gall | Refer to label for directions. Root-dip for bare-root stock. Effectiveness my be limited. Destroy infected plants. Replace with crown gall-resistant ornamentals. | ||
| Agrobacterium radiobactor Strain 84. See comments NORBAC 84 GALLTROL | |||
To ensure complete coverage of the foliage, spray roses until the fungicide drips off the leaves. Fungicide performance may be improved by adding a commercially available spreader-sticker or liquid detergent (1/2 tablespoon per gallon).
Chlorothalonil and folpet may burn the leaves of some rose varieties, especially at temperatures above 90 degrees F. To avoid this problem, use either of these fungicides at half the label rate and mix them with Benlate at 1/2 tablespoon per gallon. There are no controls for existing crown gall infections. Fumigate infested areas before replanting with roses or other woody ornamentals. Root dips of Galltrol or a similar product may be used at planting to protect roses for short periods of time.
Good sanitation practices can reduce disease problems. When buying new roses, select only disease-free bushes. Remove and destroy any plants damaged by crown gall. Carefully prune out any stem cankers on roses in late winter and place fresh mulch around the plants.
Lime sulfur (1:15 dilution) applied in late winter when the roses are dormant will also help reduce early season powdery mildew problems. Always surface irrigate roses to avoid spreading black spot and other diseases.
Mite And Insect Control
The recommendations in Table 2 are for controlling some common pests that feed on roses. Well-kept, healthy plants may not be less susceptible to insect attack, but they may recover more quickly from insect damage. Regular and thorough inspection of plants is essential if pests are to be controlled at a low infestation level.
| Pest | Pesticide | Amount To Use Per Gallon Or As Stated |
Comments |
| Aphids | acephate ORTHENE Turf, Tree and Ornamental Spray |
2 t. | Begin treatment when aphids first attack plants early in the spring. Repeat as needed. |
| diazinon 25EC |
2 t. | ||
| dimethoate CYGON 2E |
2 t. | ||
| malathon 57EC |
1 T. | ||
| Caterpillars (Bacillus thuringiensis) |
carbaryl* SEVIN 50WP SEVIN 5D DIPEL THURICIDE |
2 T. See comments See Comments |
Treat when young larvae are present. Dust lightly but thoroughly See label. |
| Bud, blossom, and leaf-feeding beetles | carbaryl* SEVIN 50WP SEVIN 5D |
2 T. See Comments |
Treat as needed. Dust lightly but thoroughly. |
| malathion 57EC1 |
T. | ||
| Spider Mites | insecticidal soap 50.5EC | 4 oz. | Follow label directions |
| dicofol KELTHANE 18.5EC |
2 t. | Keep area free of weeds. Direct spray to underside of leaves. Repeat treatment every two weeks as needed. Alternate chemicals once or twice during the season. | |
| insecticidal oil, such as SunSpray ULTRA Fine |
Use oils only under conditions listed on the label. | ||
| dienochlor PENTAC 50W PENTAC AQUAFLOW |
2 t. 2/3 t. |
Repeat treatment every 28 days as needed. | |
| Thrips | acephate ORTHENE Turf, Tree and Ornamental Spray |
1 T. | Destroy old rose blossoms. Treat every 3 to 5 days as needed. |
| diazinon 25EC |
2 t. | ||
| dimethoate CYGON 2E |
2 t. | ||
| * Watch for buildup of spider mites if carbaryl is used when
mites are present. T. = tablespoon t. = teaspoon | |||
Proper pest identification is necessary to know which chemical to apply as well as the proper application time. When spraying, thorough coverage is important in controlling rose pests. Apply pesticides only according to label directions and only when pests are present. Read the entire label.
Use pesticides only according to
the directions on the label. Follow all directions, precautions, and restrictions
that are listed. Do not use pesticides on plants that are not listed on
the label.
The pesticide rates in this publication are recommended
only if they are registered with the Environmental Protection Agency
and the Alabama Department of Agriculture and Industries. If a registration
is changed or cancelled, the rate listed here is no longer recommended.
Before you apply any pesticide, check with your county Extension agent for
the latest information.
Trade names are used only to give specific information. The Alabama Cooperative Extension System does not endorse or guarantee any product and does not recommend one product instead of another that might be similar.
For more information, contact your county Extension office. Look in your telephone directory under your county's name to find the number.
For more information, contact your county Extension office. Visit http://www.aces.edu/counties or look in your telephone directory under your county's name to find contact information.
Published by the Alabama Cooperative Extension System (Alabama A&M University and Auburn University), an equal opportunity educator and employer.
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