Wired put together a piece on dry farming and its growing profile—the obvious result of the terrible drought being felt out West. The technique known as dry farming stems from a basic philosophy: if you leave the soil free of heavy-duty fertilizers and weedkillers and pesticides, it will become more rich and not need to rely so much on loads of water to provide a yield.
In Templeton, California, Mary Morwood Hart is using dry farming on her Grenache, Mourvedre, and olive trees, carefully cultivating the soil on her 20 acres so it can sustain growth without water.
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Hart and her husband, who run the farm together, believe dry farming prolongs the vine’s life, and their method isn’t exactly devoid of moisture: The calcareous clay soils in Templeton, she says, hold a lot of water. “It creates a situation where the tap roots have to dig deep down into the soil to find moisture and it brings about character and a complexity of flavor,” says Hart. “When you do irrigate a vine, the roots tend to grow very close to the surface, because they’re just waiting there for their drops of water.”
One of the drawbacks is that the yields do not come close to matching those of typical California farms. Hart produces 1.3 tons per acre and in general California farms produce something in the ballpark of five tons per acre. But the positive effect on water consumption is noteworthy:
The effect on water usage is dramatic. According to the National Resource Conservation Service, an arm of the US Department of Agriculture, increasing soil organic content in an acre of farmland by just 1 percent can save up to 27,000 gallons of water. (Other estimates are less hefty, but still impressive.)
Another drawback is that while waterless farming works economically with high-value crops, farmers who work in crops like lettuce cannot afford lower yields. However, even they can change how they've been farming. One example is moving away from flood irrigation techniques, to ore judicial techniques like drip irrigation:
Kent Hibino has been farming vegetables at Henry Hibino Farms in the valley since 1995. He’s seen big changes in the past decade using drip irrigation. Yields are better per unit of water. And his pesticide spraying costs are down, because watering at the roots has reduced problems with mildew.
Farmers also can be more scientific about when and where they apply water. Cutting back on watering during drought-tolerant growth stages can save water and improve crop quality or yield. Adopting these steps could save 6 million acre-feet during a dry year, according to a study by the Pacific Institute. And some farmers are increasing on-farm storage—adding additional ponds as reservoirs.
California will have to be inventive as farming demands continue to grow and water seems to be more scarce than ever.