Revised
Grapes
Grapes
Dormant sprays
Apply before buds swell.
Anthracnose, powdery mildew, phomopsis, cane and leaf spot
A key pest
or pest complex
- Material
liquid lime sulfur
Grapes
Early cover sprays
Apply at bud swell, 1-inch shoot growth through first appearance of bloom.
Flea beetles
- Material
carbaryl - Comments
Larvae and adults can feed on foliage. Most serious damage occurs in the spring when adult beetles feed on newly swollen grape buds. If more than 4 percent of buds are damaged apply an insecticide.
Climbing cutworm, leafrollers, aphids
- Material
carbaryl
or malathion
or spinosad
or Bacillus thuringiensis - Comments
These pests may be present anytime between 4- to 10-inch shoot growth and bloom. Scout twice weekly. Apply insecticides only when necessary.
Spinosad for worms only.
Bacillus thuringiensis for caterpillars only.
Mites
- Material
insecticidal soap - Comments
For insecticidal soap repeat application 3 to 4 days later up to day of harvest.
Phomopsis
- Material
captan
or copper
Black rot, powdery mildew, downy mildew
A key pest
or pest complex
- Material
captan
or sulfur
or mancozeb
or myclobutanil
or copper - Comments
For powdery mildew, use myclobutanil or sulfur.
For downy mildew, use captan or mancozeb .
Captan and sulfur are only slightly effective against black rot.
Copper for black rot, downy mildew and powdery mildew.
Grapes
Bloom sprays
Apply when caps begin to fall.
Grape phylloxera
- Comments
Wart-like galls found on leaves and galls on the roots may cause vine death or premature defoliation and retarded shoot growth.
Control of the root gall form of grape phylloxera can be achieved by using rootstocks derived from native American grapes.
There is no known completely successful chemical control for the root form of grape phylloxera.
Black rot, powdery mildew, downy mildew
A key pest
or pest complex
- Material
captan
or myclobutanil
or sulfur - Comments
See comments in "early cover sprays" section.
Grapes
Postbloom, summer cover to harvest sprays
Apply 7 to 10 days after bloom. Thereafter, sprays should be applied every 10 to 14 days.
Black rot, powdery mildew, downy mildew
- Material
captan
or myclobutanil
or sulfur - Comments
Sulfur applications may injure plants if temperature exceeds 85 degrees Fahrenheit.
Grape berry moth
- Material
carbaryl
or neem
or spinosad - Comments
Infestation includes grape berries being webbed together with silken threads and turning dark purple in color. Infested berries may drop from the stems when grapes are about the size of a pea. The larvae tunnel into the berries and feed internally. Several berries in a cluster may be affected. Infested vines should be sprayed at petal fall and again 7 to 10 days later. - Days between last application and harvest
Table 2
Gray mold fruit rot
- Material
copper - Days between last application and harvest
Begin treatment at the end of bloom and repeat at 7- to 14-day intervals.
Mites
- Material
insecticidal soap - Days between last application and harvest
Table 2
Leafhopper, leafrollers, mealybugs, aphids
- Material
carbaryl
or malathion
or pyrethrins and rotenone
or insecticidal soap
or spinosad - Comments
It is important to monitor for all insect pests after petal fall, and apply insecticide as needed. Refer to product label for specific insects and harvest restrictions.
Spinosad for worms only. - Days between last application and harvest
Table 2
Rose chafer, Japanese beetle
- Material
carbaryl
or malathion - Comments
Rose chafer adults feed on blossom buds and leaves. Insecticide treatments should occur after bloom when the first adults are noticed, and if there are on average more than 2 beetles per vine. A second application in June might be needed.
Japanese beetle adults feed on the leaves and skeletonize the tissue. If about more that 15 percent of the leaves are damaged then an insecticide spray is recommended (high beetle populations may require repeated applications). - Days between last application and harvest
Table 2