Earlier this year, Gov. Newsom signed an executive order to increase California’s groundwater supply by flooding agricultural lands with rainwater from local rivers. By waiving the permits that are typically required for groundwater recharge, the plan took advantage of the state’s rainy winter — which resulted in swollen waterways and a deeper-than-usual snowpack — and turned that bad weather into a water-harvesting opportunity.
What happens if aquifers run dry once again, though? What happens if restrictions on groundwater pumping are increased? According to dryland farming specialists, there’s another way to utilize the soil’s residual moisture from the rainy seasons and maintain healthy crop production.
“Dryland farming can mean different things,” says agroecologist Caity Peterson, “but at a fundamental level, it means growing crops using primarily soil water and rainfall rather than irrigation. In California, rain comes in winter, so dryland farming here usually means winter crops such as small grains, forage crops, and pastures.”
During the years ahead, many basins in the San Joaquin Valley will likely need to reduce their groundwater pumping in order to deal with severe drought conditions and still meet the requirements of the Sustainable Groundwater Management Act. That means that certain crops may no longer be able to grow on some lands. When a large amount of farmland is retired at the same time, issues like soil erosion and dust accumulation can arise. Dryland farming — or simply “dry farming” — keeps that land viable by conserving soil moisture during long, dry periods through a system of tillage, surface protection, and drought-resistant crop varieties.
In the Mediterranean, olives and grapes have been dry farmed for thousands of years. Large areas in Spain, Greece, France, and Italy practice dry farming for those same crops. California already features many dry-farmed vineyards, including an estimated 1,000 acres in Napa. A number of other crops — including watermelons, tomatoes, pumpkins, cantaloupes, winter squash, garbanzos, apricots, apples, grains, and potatoes — have been dry farmed in California, as well.
Make no mistake; dry farming is not a strategy to maximize your yield. Instead, it lets nature dictate the genuine suitability of agricultural production in a certain region. Or, to put it another way, it’s a system of crop management that increases crop security during times of uncertain or uncertain water supply.
Can it work in the San Joaquin Valley, though? That depends on who you ask. Sufficient rainfall is required — typically 15-20 inches per year, although some experts claim it can be done with as little as 10-12 inches — which excludes areas like Bakersfield. Good soil is required, too — especially soil that retains moisture, meaning sandy soils are inappropriate. Finally, crops should be given enough space they need to pull as much water as needed from the soil, which means crowded growing operations aren’t likely to see much success. That said, California’s warm and dry Mediterranean climate does make the state a suitable candidate for dry farming.
Not ready to pursue dry farming at this moment? Remember that Fruit Growers Supply specializes in custom-designed irrigation systems that conserve water while still irrigating your crops. Give us a call today to speak with one of our experts.