Watering Without Waste
If you are watering your lawn and garden with an overhead sprinkler during daylight hours, you are wasting water. Especially from 11am and 4pm, between 10 and 20 percent of the water you apply by over-head sprinkler is lost to evaporation.
Looking for something to grow in the garden this summer now that the peas, cabbage, broccoli, kohlrabi and cauliflower are harvested? Consider growing Swiss chard, summertime lettuce and okra. Swiss chard is a great substitute for spinach, summer-time lettuce is a loose head lettuce that does not bolt easily during heat and pickled, or fried, okra always finds an appetite.
If you planted cloves of garlic in your garden last October, it should be just about ready to harvest. When you see the leaves and stems turning yellow-green and wilting, harvest time is here.
Many people irrigate in daytime to avoid disease. If the foliage of plants remains wet all day and all night, certain diseases such as mildew and fusarium can become a problem. If the foliage of plants remains wet for more than 14 continuous hours the chances for disease increase dramatically.
The solution is to delay overhead irrigating until after the night dew has dried from the leaves. That means watering from 9 to 11am and from 4 to 5pm so that the foliage can dry off before the sun sets.
The better alternative is to start irrigating after sunset and stop at sunrise, so more of the water enters the soil and less evaporates.
If you are irrigating your vegetable garden, you should consider trickle irrigation. Trickle irrigation reduces your water needs by 80 percent and can be done day or night because it does not wet the foliage.
Trickle irrigation requires laying a plastic tube along each row of vegetables and feeding water into the tube at very low pressure. The trickle tubes have holes at four- to six-inch intervals, depending on the manufacturer (www.ameleo.com or www.hummert.com).
My trickle tubes are connected to a three-quarter-inch plastic pipe header, which allows me to irrigate from one to eight rows 40 feet long at one time.
The water drips from the tubes onto the soil with little to no evaporation. Water savings are substantial, and the foliage of the vegetable plants stays dry.
Another effective method of minimizing water loss by evaporation when growing tomatoes, peppers, eggplants, cucumbers, squash, etc. is to place a gallon or larger jug near each plant. Using an ice-pick or nail, make three to five small holes in the bottom of each container. Once or twice each week, simply fill the container with water and let it drip directly into the ground.
For cucumbers and squash, I use a five-gallon plastic pail with three one-quarter-inch holes in the bottom. I fill each pail half-full with compost before placing near each hill of plants. When the plants start to vine, I add one-half cup of calcium nitrate to each pail and water heavily to mix the fertilizer with the compost. Plants that are growing vines and fruit at the same time want the additional nitrogen from the calcium.
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