Caring for grapevines isn't difficult—just restrain the impulse to make it hard. "The main thing I tell people is 'Don't panic,'" Rombough says. "'Don't freak out. Your grapes can handle an insect or two.'"
Prevent problems. Keep pests in check by attracting beneficial insects and removing infected fruit and foliage to prevent larvae from overwintering.
Keep watch. Even after you've identified a pest, watching and waiting may still be the best strategy. A study conducted by Iowa State University showed that although half of all organic vineyards surveyed had grape leafhoppers on their vines, the insects had minimal impact on the crop. Only 18 percent of organic grape growers surveyed used any kind of biological or botanical insecticide.
Use organic controls. Before you try any natural or biological pest control products, take the time to properly identify the pest and use the appropriate product—at the right stage of the pest's life cycle to make a difference. Check out Rombough's grape guidebook, the resources listed in our online grape-growing guide, or your local extension office for helpful ID and control information.
You can tolerate some insect damage without taking action, but when it comes to disease, early intervention is the key.
Know thy enemy. The diseases that afflict grapes differ vastly from one climate to the next. Your best bet is to ask other gardeners, nurserymen, or your local Master Gardener program before you plant about the diseases prevalent where you are. Cool, wet springs and mild winters in the Pacific Northwest, for instance, can lead to powdery mildew, while warm, humid weather in the East can bring on black rot. In the Southeast and California, Pierce's disease, which is caused by a bacterium, scorches grape leaves and browns their canes. An accurate ID of the problem helps you choose the right solution.
Choose a disease-resistant variety. As I've already mentioned, choosing varieties that naturally fend off diseases minimizes potential problems.
Act early. Organic gardeners have more tools than ever when it comes to controlling the common fungal diseases. Serenade, for instance, is a spray containing a beneficial bacterium that protects your grapes against three diseases: powdery mildew, botrytis, and bunch rot. It works best when you apply it as a preventative, says Pamela Marrone, Ph.D., an entomologist who founded AgraQuest, the company that manufactures Serenade.
Be vigilant. Mike Benziger, owner of Benziger Family Winery in northern California, urges gardeners to keep a close watch on grapes. "Growing organic grapes isn't hard," he says, "but it takes commitment." He recommends spending a little time with the grapes every day and training yourself to observe and spot signs of potential trouble early.
As grapes ripen, their final pigments appear—usually red, sometimes blue—and the stems get woody. Taste before you harvest; sugar content changes throughout the day and throughout the harvest season, so wait until grapes are as sweet as you'd like them to be before you pick a cluster.
Cutting a heavy, ripe bunch of grapes off the vine in the fall is the final reward of a grape grower, but then what? Grapes make a great addition to salads or as toppings on cereal or dessert. You might also want to try preserving the harvest for later in the year. The easiest way is to place dry grapes on a tray in the freezer. Once they're frozen, you can store them in a freezer bag and pop a few in your mouth anytime you want something sweet and cold. Of course, the best way to enjoy grapes is right off the vine—just ask any finch or starling!