As we head into what could become an epochal drought, despite recent welcome rains, vegetable gardeners are feeling the uncertainty. Will water restrictions snuff out the salad garden, bash beans and thwart tomato dreams?
We do know that it is typical for Central California to have great variations in annual rainfall. Our location between a wetter north and a desert south puts us at the mercy of small shifts in weather. Those of us who were living in California during the mid-’70s drought, which is about half the number of people living here now, remember the anxiety and water restrictions then. That drought did end, as did some smaller droughts later. But if climate change is under way, who knows how this one will turn out? While we can’t know what is in store, we can plan this year’s garden with care.
By all accounts, we’ve been, overall, very good at saving water in recent decades. Now it’s time to rededicate ourselves to conservation.
There are good reasons to grow your own vegetables and herbs. You can do so using much less water than the average large-scale farm; you save the Earth part of the carbon cost of transporting your food, and it will probably inspire you to eat more vegetables.
Here are some tips to help you plan a food garden in a drought:
— Start by conserving water indoors. Fix leaks, avoid running water wastefully and take advantage of whatever water-saving appliances you can obtain.
— Look to your soil. Add several inches of organic matter, compost or other amendment once or twice a year. This will greatly increase the soil’s water-holding capacity. But don’t add too much. More than 5 percent organic matter can create conditions that are not healthy for plant roots.
— Think about what and how much you will actually eat. If you gardened last year, think back to whether you wasted food that you grew, and use that as a guide to plan this year’s garden to better match your needs.
— Plant some crops in February or March to take advantage of any rain we get this season, as well as of the slower evaporation rate of cooler weather. Planting in August through November (depending on crop and location) can take advantage of cooler fall and winter temperatures and possible rainfall in the same way.
— Plant closely enough together that mature neighboring plants touch leaves.
— Apply an organic mulch, using a fine-textured material that can decay as time passes, rather than large bark chunks. Keep mulch back from plant stems to prevent their decay.
— If you choose not to plant some of your food gardening area, water it well, cover it with an organic mulch and, if allotments allow, water it well one or two more times in the summer to keep your soil alive.
— Water early or late in the day, when evaporation is at its slowest, and water at or near the ground rather than with a high, evaporation-prone spray.
— If you water by hand, once your crops are past the seedling stage, water crops deeply, then don’t water again until the top inch of soil is dry. Use a moisture meter to check soil moisture. Put a simple timer on your hose at the faucet so you can set it to turn off the hose automatically.
— If you choose drip irrigation, use a separate program for vegetables, which require more water than your drought-tolerant ornamentals. Pin drip lines to the ground to avoid water running unevenly along the lines. Provide manual shutoff valves for separate beds, so you can turn off the drip as you change crops – or to let onions or garlic dry out.
— Get a programmable irrigation timer with a rain sensor, and be sure it’s on, so you won’t waste water during a storm. Get friendly with the manual that comes with your timer, so you can reset it during the year to account for changing temperatures and day length, and know when and how to replace its battery. If you lose the manual, use the make and model to print out a replacement from the website of the manufacturer.
— Gray water, reused household water, can irrigate ornamental plantings and fruit trees, freeing clean water for your food garden vegetables, but is not recommended for use where it may contact edible parts of food. If you do consider installing a gray water system, be sure you find professional plans for doing so, as poorly planned systems can clog the plumbing almost immediately.
For more drought tips and news, go to www.sfgate.com/drought.