permaculture.. Farming without water

To help people understand how dry farming works, Little often evokes the image of a wet sponge covered with cellophane. Following winter and spring rains, the farmer will cultivated and break up the soil to create a moist “sponge.” Then the top layer is compacted using a roller to form a dry crust (the “cellophane”). This three- to four-inch layer, sometimes referred to as a dust mulch, seals in water and prevents evaporation.

“It’s very challenging because you have to hold the moisture for long periods of time, and you don’t know how different crops are going to react in different areas,” Little says. Much of the land he farms is rolling hills and valleys, which present additional challenges because they hold and move groundwater differently than flat land.

Deprived of any surface irrigation, dry-farmed plants develop deep, robust roots to seek out and soak up soil moisture. Because they absorb less water than their conventionally irrigated counterparts, dry-farmed crops are characteristically smaller but more nutrient-dense and flavorful.

“When you water a tree, it dilutes the flavor a lot in some cases,” says Stan Devoto, who dry-farms more than 50 varieties of heirloom apples at Devoto Gardens. “Instead of having a really hard, crisp, firm texture, your apple will be two or three times the size of a dry-farmed apple, and you just don’t get the flavor.”

Devoto has been dry-farming in Sebastopol, Calif., since the 1970s. “We had no choice,” he says. “There’s just not enough water. Pretty much all the orchards are dry-farmed, with the exception of the orchards where trees are planted super close or use dwarf rootstock.”

Having wide orchard rows, which allow tree roots to spread out, is essential for dry-farming apples, as is thinning (removing much of the fruit early in its development) to ensure that each apple gets as much water as possible. In drier years (like this one), Devoto must work extra hard to control weeds, which drink water needed by thirsty trees. As the summer progresses, the ground slowly dries out, stressing out the fruits as they ripen, which helps the sugars become more concentrated.

But while water conservation and intensely flavorful crops are the clear benefits of dry farming, the major tradeoff is yield. Devoto says that apple growers in West Sonoma County, which was once home to a booming apple industry, only get about 12 tons per acre, compared to 30 to 40 tons produced by large apple farms in the state’s Central Valley.

Similarly, Joe Schirmer of Dirty Girl Produce says that his famous dry-farmed Early Girl tomatoes sometimes yield only about a third of what their irrigated counterparts produce. Meanwhile, Little estimates that he gets about a quarter to a third the yield of large organic potato growers. “It it’s hard to compete with some of these big organic farms that are watering,” he says.

Without irrigation, his crops are at the mercy of seasonal rainfall and varying soil conditions from year to year. “You’re on the edge constantly, and one little thing could tip you over,” Little reflects. “We’re barely making it, really, but I believe in coastal farming. I believe we’re going to come back to it.”

While dry farming has geographic limitations, it could pave the way for more coastal agriculture and offer techniques for farmers in drier areas to farm with less water. “The coast of California used to be our main source of food in the state, until they started developing farms in the Central Valley because of all the water,” Little continues. “Now they’re running out of water.”

Devoto’s Gravenstein apples are coming into season as we speak. They may not be picture-perfect or super large, Devoto adds, “But the flavor is just phenomenal.”