One of the more challenging skills for a new gardener is knowing how to water the garden. Offhand, one would think, “How hard can it be?” Yet, this is an acquired skill. No one has it “straight out of the gate.” Many new gardeners suffer needlessly because they don’t know the basic principles. I believe this is a neglected area of instruction, 1) because experienced gardeners often know and assume that everyone else does too, and 2) because new gardeners usually don’t know enough to know that they need to learn this!
Knowing how to water the garden is an acquired skill.
If you don’t water correctly, you may invite disease and crop failure into the garden. Either too much or too little irrigation can be damaging. So, without further comment, let me give six principles for effective watering.
1. Water when needed, and only when needed.
Too many people water on a schedule or only when there’s a crisis. One should only water when it’s needed. Those who automatically go out to the garden, every evening and water, may be harming the garden more than helping. The moisture doesn’t need to be on the surface, which is where most people focus. It needs to be a several inches below the surface. So, before watering, check and see if it is necessary. Dig down 3-4″ and see if the soil is moist or dry. If you get 3-4″ down, and it’s dry, then you need to water. Another hint might be that certain plants are wilting during the heat of the day and recovering in the evening.
2. When you water, water deeply.
Chances are, if you water while holding on to the hose, you don’t water deeply enough. Very few have the patience to water in one spot, long enough to water properly. How long the water should remain set over a given area depends a lot on the type of soil, the flow of water, natural precipitation, temperature and coverage of the watering mechanism. It’s nearly impossible to prescribe a time without knowing all these factors, but you can experiment. If using a sprinkler, start out by leaving it in one spot for two hours. Turn off the water and wait an hour to let things “settle,” and then dig down to see how well the water penetrated. If possible, dig down a foot. If you hit powdery dry soil I’d recommend at least another hour of watering, then, check again.
Shallow watering causes plants to lose their resilience.
When one waters shallowly this encourages plants to keep their roots near the surface, in the area which normally dries out the soonest. Then, when the irrigation stops, the plants can’t reach deeply for the moisture which might be only a few inches below their roots. Deep watering followed by drying, before more irrigation encourages the plants to sink their roots deeply, increasing their resilience, and possibly even their ability to reach necessary nutrients.
3. Know your soil.
Different soils handle moisture differently. Ron Cook and I live only a couple miles apart. When we receive 2″ of rain at night, I’m excited. I know that when I get off work the next afternoon, the soil in my garden will be PERFECT for weeding. Ron, on the other hand, has to stay out of his garden for a couple days. His soil holds the water so well that it’s going to be MUD for a while! About the time he can just get into his garden, my garden is starting to get dry and I’m thinking about watering. By comparing our two gardens, it’s easy to see why garden instructions which say to water every two or three days, once a week, or to apply a certain amount of water can be problematic!
4. If possible, water in the cool of the day.
There are different opinions as to consequences of watering during the hottest time of the day, and I’m not convinced that some of those differences aren’t based on regional and climate differences. Everyone should, however, agree that more of the water will sink in, and less will evaporate during the cooler times of the day (morning, night or evening).
5. When watering is needed… water.
I don’t know how many times I’ve held off on watering because it looked like it was going to rain, only to be fooled. If you have a busy schedule like me, and you determine that you need to water, just do it.
6. When possible, mulch.
Mulch not only improves the soil, it also saves on watering by conserving moisture.
Different Kinds of Irrigation
- Overhead watering: This is the most common form of irrigation and been used, perhaps the longest in North America. Sprinklers can be moved around easily, though they may be somewhat inefficient, throwing water where it is not needed.
- Soaker hose: There are a couple of styles of soaker hoses. These have the advantage of placing the water right at the roots of the plants (if they’re planted in a line). When it’s possible to use them, soaker hoses are more efficient than overhead watering. They can also be moved. Disadvantages: 1) They can be pricey. 2) They’re very susceptible to rodent damage, and once damaged, they’re very difficult to repair.
- Irrigation Tape: This form of irrigation is wonderful! Irrigation tape is flattened with holes every so many inches. When water pressure rises, the tape expands and drips water right below the tape. We use this in combination with a plastic row cover for HUGE crops of sweet potatoes. Irrigation tape can get accidentally cut or gnawed by rodents, but one can hear the leak, as it sprays, and it’s easy to fix with electrical tape. This form of irrigation can be intimidating due to hardware needs, but it’s really not hard, it’s economical and effective.
An Example of a Irrigation Tape Starter Kit
(Disclaimer: We haven’t used this company.)