Extension Service Garden Hints

How to cut water use in the garden

CORVALLIS- Oregon's summers are ordinarily quite dry compared with other parts of the country, even in normal years. This year, climatologists are predicting that Oregon may suffer from severe drought conditions. Home gardeners in Oregon are heavily dependent on watering gardens in the summer, rather than waiting for rain, drought year or not.

The Oregon State University Extension Service's Master Gardener Program has worked for decades with home gardeners to help them learn to use water more efficiently. Here are some ideas OSU Master Gardeners recommend to help people use water more efficiently in the yard and garden in dry times. It is good to think about these things in the early spring, when you are planning and planting your summer garden.

Plant in closer rows. A smaller area gardened more intensively will produce more vegetables relative to the amount of water applied. You can grow quite a few vegetables much closer together than traditional 2 1/2- to 3-foot rows. You can place radishes, onions, beets, carrots and other root crops in wide rows, at in-row spacing. For example, plant your carrot seeds in grids two inches apart. This way, you make better use of the water you apply in the root zone. In addition, a shaded soil loses less water by evaporation to the atmosphere.

Growing flowers and vegetables in the ground, rather than in containers, helps save water. Soil in containers dries much faster than in garden beds and rows.

Apply organic matter to your soil and mulches on top of the soil to help the soil retain moisture and keep weeds at bay.

Try to concentrate watering in the plants' root zone. The less water you apply between the rows where roots can't use it, the less water lost to evaporation and into the ground. As much as 25 percent of the water applied in overhead sprinkling is lost to evaporation, especially during the hot part of the day, from noon to 6 p.m.

To help keep the water in the root zone, try these ideas:

Take the top off an empty large juice or coffee can, then punch holes in the bottom of it. Then bury the can in the ground so the bottom of the can is adjacent to, and at root level of the plants you want to water. Pour water in the open top and it will reach the roots with a minimum of loss. This works well with squash or other plants grown in a cluster or hill.

Or use a plastic milk or juice jug in the same way, punching holes in the bottom, putting it next to a plant, taking the lid off and filling it with water. Put the cap back on and you will slow the watering process down, which is good.

Irrigate individual plants like tomatoes, peppers, and eggplants in the same manner, using a slightly smaller can. Punch the holes in the can only on the side next to the plant.

A "trickle" or "drip" irrigation system permits water to ooze from a continuous soaker, or it emits water at a given location. You can buy kits with various components to supply water in this fashion at garden stores. Canvas soakers, black rubber "seeping" hoses or inverted sprinkler hoses near the plants, perform the same function. These types of delivery can save you many gallons of water and are easy to install.

If you use sprinklers, help minimize water losses by these methods:

Sprinkle the garden, not the surrounding area.

Water early in the morning when the air is cool, the wind is low and the water pressure is better on municipal systems.

Keep an eye on the water. Is it soaking in or running off? When it runs off or pools on the surface, the ground may be saturated. Stop sprinkling. Place used tuna cans around the garden to see how much you have sprinkled. Oftentimes, an inch is enough.

It is better for your garden plants to thoroughly soak the soil to a depth of six to eight inches and do it less frequently than water lightly and more often. With fairly mature plants in cooler weather, a five- to seven-day interval may be enough. But with younger plants or hot weather, more frequent watering will be necessary.

After watering, it is crucial to monitor how deep the water has percolated. Take a shovel and see if the moisture has seeped as deep as the root zone of the plants you are watering. If the root zone is still dry, your plants need more water. Adjust watering time. Eastern Oregon sandy soil is much more porous than clay and loam soils of western Oregon. And water will penetrate clay and loam more slowly than sandy soil.

For more information about efficient watering, the OSU Extension Service offers "Growing Your Own," and "