For many weekend gardeners, the plant watering process goes something like this:
1. Turn on water valve.
2. Direct nozzle of hose in direction of plants and squeeze.
3. Spray until arms tire.
4. Turn off valve and give hearty pat on back for job well done.
Another popular method, particularly in our little corner of the world, is the following:
1. Wait for a rainy spell and hope for the best.
It’s easy to forget that despite their conspicuous lack of emotive expression and conversational skills, plants are living—some would even say, sentient—organisms that require no less nurturing and nutrition than any other creature in order to prosper. (I do not, of course, include weeds in this category, as they, like cockroaches, seem fully perfectly capable of thriving on nothing but pure spite.) For vegetables in particular, water is like mother’s milk; it should be administered liberally and often.
So even if you aren’t sold on the idea that murmuring sweet nothings to your plants will help them grow (conclusive results are still pending on that one, anyway), you can still do the right thing by making sure that they’re well watered. And while you’re at it, you may as well throw in some sweet nothings, too.
1. Plants can absorb food from the soil only if it is in solution. So in effect, plants must have damp feet in order to eat.
2. A desert is usually rich farmland that happens to be lacking water. If you add water by irrigation, those arid lands will bloom. Only land whose topsoil has eroded or that has poisonous materials in the topsoil is true desert. Water supply and temperature are the two great determinants of what plants can be grown where.
3. The best time to water is in the morning. Plants do most of their growing during the day and need the water for photosynthesis. Watering in the morning also allows plants to dry out by evening, which reduces the chance of mildew and rot.
4. Mulching helps to keep soil moist as well as to suppress weeds. (But wait until the ground gets thoroughly warm before putting on mulch.)
5. Plant species differ a lot in water requirements. Vegetables need a lot of water; most vegetables are about 85 to 90 percent water. Flowers, trees, and bushes can all survive longer without water than vegetables.
6. Erosion happens when wind or water moves soil. If you garden or farm on sloping land, you risk erosion. Grass planted in strips across slopes, summer mulches, and winter cover crops help prevent erosion. Strategically placed diversion ditches also help.
7. Watering must be faithful. If stunted by water shortage, many vegetables never grow normally again.
8. Watering needs to be generous. Almost all vegetables produce much more with abundant water than with a skimpy supply. For a minimum, your garden needs about an inch of water a week, from either the sky or your irrigation system.
9. Surface runoff, puddling, and evaporation are all wastes of water.
10. For newly planted seeds, water often enough to keep the soil continuously moist—morning and evening, sprinkling every day until they are up. You want them to come up as fast as possible. The moist ground also helps discourage wild birds and the family poultry from digging up the seeds and eating them.
11. Once your plants are well started, give them a good soaking rather than morning and evening sprinkles. Light sprinkles encourage shallow root systems because unless the soil gets wet to the level of the deeper roots, the shallow roots develop at the expense of the deeper ones. But those shallow roots can’t do as good a job of finding soil nutrients. Because the surface of the soil dries out faster than the deeper soil, shallow watering also creates a vicious cycle in which more frequent watering is needed to keep the plants from wilting. Deep soakings, on the other hand, encourage deep root systems, and deep roots don’t have to be watered as often.
12. For that “deep” watering, you want to water until the soil is wet to a depth of 4 to 6 inches. How long that takes depends on how fast your irrigation system delivers water and how fast your soil type absorbs it. When the soil gets dry, water again, to a depth of about 4 inches.