Even in parts of the country where rainfall is substantial, gardens parch quickly. In regions where water is scarce, keeping the garden well hydrated becomes a science experiment.
Plants lose water through their leaves by a process called transpiration. The soil also gives up moisture by evaporation. Together, these processes, called evapotranspiration, can mean a thirsty garden.
When to Water
There is no set rule. Some parts of the garden need watering daily, others three times a week and others weekly. During a summer drought, you might need to water more often. Of course, if the drought is severe, you should follow restrictions ordered by your municipality. Do not waste precious water on a lawn or flowers!
Containers require more frequent watering than gardens because the soil dries out far faster — and hanging pots need even more watering than standing ones. Depending on where you live and the amount of rainfall, you might get away with watering your pots daily and your garden weekly.
Established lawns green up quickly, and so if you notice yours looks brown and dry, a good soaking should bring it back. Or a good rainstorm. On the other hand, if your town restricts lawn watering because of summer water shortages, don’t worry too much. The lawn will survive without water for quite awhile and once restrictions are lifted, it will quickly bounce back bright and green.
Water early or late in the day. When the sun rises high in the sky, the water will evaporate far more quickly and so midday watering is often a waste of time and water.
Some gardeners prefer the early morning for watering because nighttime moisture can attract slugs, which eat plants.
Hoses and Sprinklers
For containers and very small gardens, a hose with a spray wand is all you need. For all other watering, sprinklers or soaker and porous hoses work better.
Oscillating sprinklers are the most effective devices for watering lawns and many gardens. Old-fashioned sprinklers that don’t sweep the area are adequate, too, and rarely clog, but you will have to move them around the yard for good coverage.
Soaking and porous hoses, which snake through the garden and slowly release water, arguably are the most efficient way to water your plants. Vegetable gardeners in particular prefer them. (Flower gardeners don’t always like the way they look, since most gardeners leave them in place for the entire season.)
Soaker and porous (or oozing) hoses lie flat and have small holes along their lengths. Tiny spurts or drips (for a soaker hose) or oozing tears (from a porous hose) hydrate the soil.
The slow soak reaches root hairs and surrounding soil and promotes good, steady growth. Wind and sun don’t reach the water as readily and so little moisture is lost. Talk to a knowledgeable person at the garden center when you buy one of these hoses.
Finally, knowing how often to water is a puzzle. Seasoned gardeners can usually tell by looking at their plants. In arid parts of the country, the newspaper and local Internet sites provide the evapotranspiration rate and gardeners can use it to determine how much to water.
When you water, don’t be stingy. Give the plants a good long drenching. Too little water is almost no help at all. With a little trial and error, you will learn when your garden needs to be watered and will know how to keep it happy. On the other hand, you will learn not to waste water by drenching the garden, the lawn, and containers early or late in the day and only when necessary.