Harnett County Center
ALL ABOUT LANDSCAPE IRRIGATION, 11/20/98
Although you may dread the cold, rainy, and dreary days we normally have in November, I welcome them after the dry summer we just endured. To me, it's comforting to know that ponds are being filled, groundwater is being recharged, and plant roots are drinking deeply.
It was a challenge to provide our landscapes with enough water during those hot, dry months. The key to success, however, is not an unlimited source of free water. It's knowing the best method and timing, and applying the right amount.
HOW MUCH?
I've often given the rule of thumb of an inch of water per week. This applies to most of our landscape and garden plants. Coincidentally, it happens to closely match the average amount of rainfall we receive in North Carolina. Well, perhaps that's not such a coincidence.
And although rules of thumb are nice, they only go so far. Keep in mind that trees, for example, have very extensive root systems and can tap into water resources from a large volume of soil. Your newly seeded lawn or the dogwood tree you just planted, however, will likely need more than an inch per week.
As new plants are getting used to their environment, they need a bit of extra water. But once plants become settled in, it's good to cut back. If you baby your plants, they will always need babying. They will develop a very shallow root system, which makes them even more susceptible to drought.
If, however, you water less frequently, your plants will put out deep, strong root systems that will help them thrive.
Also keep in mind that some plants tolerate drought better than others. Daylilies, for example, could just about grow in a desert. A hibiscus, on the other hand, prefers a lot of moisture. Observation and reference can help you determine how much your plants need.
HOW OFTEN?
Keep in mind that watering according to a set schedule, say every Tuesday and Thursday, is less than ideal. The key is to give plants water when they need it. I know that's stating the obvious, but it requires a bit of observation.
There are ways to tell when a plant is suffering drought stress. Probably the best method is to feel the soil. And I don't mean placing your hand on top of the soil. You have to dig down at least a couple of inches. The surface may be dry as a bone, but if there is moisture at two inches, your plant is probably okay.
If you have an automatic irrigation system, it's easy to set the timer and forget about it. How many times have you seen an automatic irrigation system running while it was raining? So don't let your automatic timer become a substitute for observing your landscape.
WHEN TO WATER
Watering during the middle of the day is quite wasteful, as a large portion of the water applied is lost to evaporation. Watering late in the day, however, could leave the foliage wet, which can encourage fungus diseases. So the best time to water is late at night or early in the morning.
I certainly hope that next summer is not a repeat performance. But even if it is, these tips will help your plants get through it, and may even help you cut down on your watering. And saving water helps us all.
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