Once your vineyard has been trellised, and your grapes planted and pruned, there are nevertheless many challenges to getting a good provide and a quality crop. A number of different pests can move into your vineyard, reduce production, and already kill your vines.
Most diseases affecting grapes are types of fungi which seem to love grapes. As a grower, you will have to monitor your vines for any signs of infection. Black decay will show as small reddish-brown spots 1/8 to 1/4 inch in diameter on the lower leaves, in early summer. The lesions develop a black border and a black pimple in the middle. Downy Mildew is extremely serious and will cause a large crop loss. Fruit clusters will be covered with a white growth in late spring. In mid summer it will show as 1/8 to 1/4 inch pale yellow lesions. Powdery mildew will show in mid summer as a white powdery growth on the top of the leaves. There are numerous other fungi and mildew of lesser importance. All can be controlled with a variety of different fungicides.
Insects that Love Grapes
Vineyards provide a real feast for a number of insects so you must keep an eye out for them or the damage they cause. Grape leafhopper adults are orange-yellow with some dark spots and yellow lines on their wings. They satisfy on the leaves and you will notice yellow stippling along the leaf veins. The Japanese Beetles have a copper colored back and green neck and head. These bugs eat the complete leaf except for the vein so photosynthesis comes to a stop. Grape berry moths have a copper colored head and their wings are black with a pretty copper design. They lay eggs on the grapes and in less that a week the larvae hatch and bore into the grape. Rose chafers are pale green to tan in color with reddish brown spiny legs. They eat the grapes and are found in late spring and early summer. All these insects can be controlled with various insecticides, but often the damage is minor if the insect population is not too large.
Birds also Love Grapes
Birds are a major threat to your vineyard if they are a species that flock near harvest time and eat fruits and berries. European Starlings, American Robins, House Finches, and Cedar Waxwings are the biggest pests. Some birds such as Red-winged Blackbirds and Goldfinches are a big help since they eat insects and don’t eat the fruit. There are a number of ways to scare the birds and this will work if it is done early when birds just begin to find your juicy grapes. If they start to flock and eating your grapes become habitual, you won’t have much luck. Now about the only different is a large net placed over your trellis.
In early spring, look for deer who love the new shoots. You will know you have deer problems if the deer high shoots are broken off approximately since deer without upper incisors. If you have a large deer population, this can be a major problem. The most effective method is using odor repellents. The most effective scent is the coyote although human or dog scents will also work. Your other main different is an electric fence, or an 8 foot high standard fence.
The whole secret to any of these pests is identifying the problem early and solving the problem before a lot of damage is done. If you can harvest 80-90 percent of your projected crop, you will have an noticeable year and can begin the grind with a smile on your confront.