|My husband and I are debating on whether or not to get an automatic sprinkler system. Although we often don't get much rain during the summer months, this year has been especially hot and dry, and we find ourselves spending a lot of time watering our vegetable garden, as well as our trees and shrubs.
Can you give us any pros and cons about installing an automatic sprinkler system? Would we be better off installing drip hoses throughout our vegetable garden? What's the best way to water trees?
|I would not recommend a sprinkler system for your vegetable or flower garden. Drip irrigation would be preferrable, as it puts the water on the soil, not in the air or foliage or tree trunks. Water splashing on the soil, then onto foliage, can spread fungal diseases which are hard to eradicate. Also, much of the sprinkler's water can be lost to evaporation before it gets to the soil and the roots, where you want it to be.
Once established, most trees will not need a lot of supplemental irrigation, depending on weather conditions and the tree's appropriateness for your climate. Trees develop shallow, spreading root systems in the top two feet of soil and have few deep or "tap" roots. To water new trees, create a wide but shallow "moat" around the trunk by building up 3- or 4-inch circular berms of soil, the first one a foot or so away from the trunk, the second a foot or so out. You can fill this donut-shaped area with water, and it will slowly seep in right where the roots need it. The goal is to keep water away from the trunk to discourage disease.
Deep, infrequent irrigation is preferable to frequent, shallow sprinklings, which do more harm than good. The soil should be moist to a depth of at least a foot, preferably 18 inches. To determine how far water has penetrated, poke a soil probe (a long metal rod or screwdriver) into the soil. It will move easily through moist soil, stopping abruptly where soil is dry. As trees mature, expand the watering zone beyond the tree's canopy (or dripline), which is where roots are actively growing.
I think a good drip system with a timer for your garden and flower beds would be your best bets. You can include the individual trees in this set up, or use the moat technique above.