Driving home two weeks ago, I saw that a familiar sight had returned. My town’s ‘welcome to’ sign had an addition, “Mandatory Odd Even Watering”. A week later, there was another addition: “No Outdoor Watering 9 a.m. to 5p.m”. A wet spring had given way to a dry summer and water supplies could no longer keep up with demand.
As a homeowner with a two-acre garden, a vegetable garden, and 50 containers, how can I keep everything alive?
Over the years, I’ve developed strategies that not only keep everything alive, but also keeps my work load low. The first priority for water is the vegetable garden. Almost all vegetables are annuals and, if they get stressed, you get no tomatoes or lettuce, zucchini or corn. When you water your vegetable garden, water it deeply. A quick, light watering may make the soil look wet but, if it hasn’t penetrated several inches, your plants will be in trouble. Shallow watering ‘teaches’ plants to keep roots at the surface. When the 90+ degree days arrive, the top few inches of the soil dries out quickly and the shallow rooted plant suffers.
Deep watering trains those roots to follow the water. Check with your trowel to make certain the water has penetrated four inches or more. But go a step further: after that deep watering: lay down mulch between the rows of vegetables. A layer of newspaper covered by straw, dried grass clippings, wood chips, or even more soil keeps the water from evaporating and your roots wet longer. While mulch should never touch the stem of any plant, you can put it under squash, cucumbers and others that spread over a wide area. Even on the hottest days of summer, this will keep your garden moist for two to three days.
The next priority for water is newly planted trees and shrubs. It takes a tree two to five years to establish a good root system after transplanting, a shrub takes one to two years. I give new shrubs regular watering for one year after planting, trees for two years. I make the most of the water I use by applying it through slow-drip bags (available from garden centers and online). These bags release water over a number of hours directly into the drip zone. A drip hose circling the plant and running at low pressure for several hours can do the same thing, ensuring every drop feeds the roots with no runoff. Trees and shrubs should be mulched with two to four inches of mulch, making certain it doesn’t touch the trunk of the plant. If you use the mulch to create a shallow saucer around the plant, it will help preserve rainwater by preventing run-off during storms.
Container gardens need extra attention during extreme heat. The container and soil heat up rapidly, making life even harder for the plants. If they can be moved into shadier areas, even the sun lovers will thank you. Check pots each day, especially if they are small. Water thoroughly until you see water come out of the bottom of the container so you know the soil is soaked through. Remember that rain does you container little good if the water hits the leaves and runs off onto the pavement or ground below. The good news is that containers make very effective use of water. During the hottest part of July I soaked fifty medium-to-large containers every other day. Total water used each time: about 50 gallons.
Perennials also need regular watering that first year. Once established, perennials can go several weeks without rain and suffer no serious harm. Don’t be fooled into rushing for the watering can by a plant that seems wilted during the middle of the day: think how you feel when standing in full sun on a summer afternoon. Plants are under stress only if they appear wilted in the evening or morning. Drip irrigation is again the best way to put the water where it is needed without waste. A sprinkler, running in sunlight, loses half the water to evaporation before it hits the ground. Hose watering is your next best choice, particularly if done first thing in the morning when the plant can take up the water before the heat becomes too intense. Wet leaves at night are a breeding ground for mildew and other diseases.
How much water do you have available to put on the garden? More than you think if you use a few old fashioned strategies. Put a water barrel on any or all of your downspouts. A quarter-inch inch of rain is barely enough to wet the soil but what comes off your roof will fill a 55 gallon rain barrel. The barrel’s spigot can then be attached to a drip hose for no-effort watering of an area or used to fill jugs to water your containers. Don’t let water go needlessly down the drain: it probably takes one to two gallons of water to get hot water up when you shower in the morning. Put a bucket under the faucet and you’ve saved that water for the garden. Keep a bucket in the sink when washing fruits and vegetables. Your plants won’t mind a little dirt.
You’ll notice that I haven’t said a word about lawns. That’s because the biggest water saver of all is skipping watering the lawn. Lawns will go dormant, which is what they want to do in extreme heat. When the rains return, they will quickly return to their green selves no worse for the summer nap. When you mow, keep the blade on your mower to at least three inches and your lawn will stay greener, longer.
Finally, plan for future dry summers by using native plants. Natives have evolved to handle our hot, dry summers and our cold, dry winters. They require less work on your part and are more likely to survive for a long and happy life in your garden. Once considered “weedy” plants with no place in the homeowner’s garden, horticulturalists have bred them for larger flowers, more colors and in compact sizes making them the perfect for everyone.