Growing Grapes

Whether destined for wine or eaten straight off the vine, grapes are a natural for Santa Barbara County gardens.

There’s plenty of precedent.

Both wine grapes and table grapes have been cultivated for thousands of years in other Mediterranean climates. In California, Franciscans planted grapes at the missions that Father Serra established in the late 1700s.

Today, you might be inspired by the orderly rows of wine grapes marching across local hillsides. You may crave crisp, sweet grapes, plucked fresh from the garden, or a shade-covered arbor.

Whatever your desires, It’s important to match our coastal conditions with the dozens of grape varieties available.

By Way of Background

Simply put, grapes are berries produced on deciduous, woody vines. The two species common for consumption are European grapes (Vitis vinifera) and American grapes (Vitis labrusca). A third group, American hybrids, are crosses between the two.

European varieties are the most widespread wine, table and raisin grapes grown in California. But they require hot summer nights and a long growing season, and are prone to powdery mildew, a fungal disease that can distort and damage the fruit. Afflicted vines are to be dusted with sulfur every two weeks from spring until harvest.

American varieties are favored for table grapes, raisins, jelly and jam. They are better suited to our coastal climate as they bear well during shorter seasons and cooler temperatures, and are not as susceptible to mildew.

It’s important to note that while daytime highs in our inland valleys and canyons may match temperatures in the San Joaquin Valley — where Thompson Seedless grapes reign supreme — our nights are considerably cooler. Those night-time temperatures are why cool-blooded Americans are a good match.

American hybrids can be more easy-going than the Europeans, too. Some bear less disease-prone wine grapes; others produce flavorful table grapes.

In addition, our native California wild grape (Vitis californica) bears tiny fruit that’s edible, but more likely to provide sustenance to birds than humans. Roger’s Red is an especially beautiful selection that creates summertime shade and reliably turns bright red in fall.

What to Grow

Wine grapes are generally small and bear seeds, while their thick skins contribute to the aroma of wine. Table grapes are larger, often seedless and have thin skins.

Unless you’re determined to replicate a vineyard planting and willing to tackle the difficulties of cultivating wine grapes, table grapes are an easier bet.

American and American hybrids for the Central Coast include dark purple Blueberry, Concord and Mars; red Canadice, Catawba, Suffolk and Vanessa; green Himrod, Interlaken and Niagara; and yellow Golden Muscat.

You may find success with a few European table grapes that prefer cooler temperatures, such as Black Monukka, a seedless purplish-black; and two greens, Muscat of Alexandria and Perlette. Avoid heat-loving Thompson seedless unless you value its super-sized leaves, which are ideal for Middle Eastern dishes that require stuffing grape leaves.

Planting Time

All grapes need fast drainage and some summer heat.

Choose a sunny spot with the most gritty, sandy, minerally soil possible. It doesn’t have to be particularly fertile: you can amend and mulch with compost to boost nutrients.

If yours is thick, adobe soil, plant your vines in a raised bed or on tall, broad mounds or a steep slope. Otherwise, your vines may thrive for the first few years, then slowly decline as the heavy soil inevitably swallows them up. Even in the best draining soil, plant your vines a few inches high to allow for settling.

Also provide support. Space your vines at least 8 feet apart, then train them on a few strands of galvanized wire strung between freestanding posts; on a broad, sturdy trellis; or up the posts of a pergola or arbor. Install the stakes at planting time. Although it will take several years for your vines to be completely up and growing, driving a stake into the ground later on could damage the roots.

Ongoing Care

It may take up to five years for your first harvest.

During the first summer, water your vines every week and loosely tie up any branches that flop on the ground.

Just before your vines break dormancy the following spring, start pruning to create the scaffolding branches that push out the smooth, year-old wood that bears clusters of fruit.

Correct pruning is key. In local vineyards, balancing foliage and fruit is an art, developed over years of practice by vintners to create world-class wines.

In the home garden, pruning presents a mind-blowing number of options. It’s a tedious, multi-year process and varies based on whether you’re using posts and wires, or covering a fence or arbor. Some vines require pruning canes; others require pruning spurs.

Detailing each specific technique would be mind-numbingly boring unless you’re out there wielding pruners at this particular moment. Instead, arm yourself with a good pruning book or directions from the internet. An excellent place to start is UC Cooperative Extension’s California Master Gardener Handbook or website, ucanr.org.

Harvest

Grapes turn color well before they’re ripe, and once picked, they don’t continue to ripen. So pick a few to check their flavor before harvesting full clusters.

Also don’t worry if your grapes aren’t as plump as those at the supermarket. Many commercial growers spray growth hormones to expand the fruits’ cells. That changes the appearance, but not the sugars. Your grapes may be smaller, but they’ll be just as delectable — if not more — because you’ll be able to harvest them at their absolute peak of freshness.

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This article was first published in the Spring 2013 issue of Edible Santa Barbara.

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