Self-Watering Containers

How to grow incredible vegetables in Self-Watering Containers
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A self-watering container is perfect for a container garden. A container garden needs to be watered more often than a traditional garden planted in the ground, partly because the plant's roots are confined to a much smaller area and cannot simply go deeper to find moisture as they can in the earth. Also, the sides of the container itself absorb heat from the sun which speeds up the evaporation process. Large nursery pots or flower pots work well for container gardening but they require more attention than a self-watering container. You can alleviate some of this extra work by using a saucer, tray or other shallow container under the pot to catch and hold a small reservoir of water. This solution is not without its own problems, though. During a long hot dry spell, you may have to water a container more than once a day when the plants are mature and in heavy production. The addition of a saucer or tray may let you water just once or twice a day, depending on conditions. However, the biggest problem is that the plant roots are always in a state of either soaking wet or too dry. There is no middle ground at all. Self-watering containers are designed to solve this problem of extremes.

Commercially available self-watering containers provide an extra bit of help with the problem of proper watering. They have a built-in reservoir for water storage and use a wicking system of some type to keep the soil around the roots of the plant properly moist. This wicking system can be either an obvious wick made of a sheet of non-woven material that dips into the water and draws moisture upwards or it may be a column of soil that is actually contacting the water and acting as the wick. A good commercial self-watering container also includes an overflow outlet so that excess water can drain off rather than drown the plants in rainy weather.

Self-watering container, in green or terra cotta. Buy now!

Another feature of a good self-watering container is the small air space between the soil and the surface of the water. The plant can put down specialized roots to tap directly into the reservoir but the soil is never soggy. A self-watering container takes the guesswork out of your watering routine.

You can also create your own self-watering containers with a few commonly available materials, a bit of ingenuity and a little effort. Remember that the idea is to form a reservoir for holding water, with an overflow hole and a wicking system, in addition to a small air space.

To help you get started, we have a design developed by the University of Maryland that you can make yourself. It not only serves as a self-watering container for plants but also conserves the run-off from the overflow hole, thereby letting you recycle any fertilizer and nutrients that would otherwise be lost during rainy weather or the occasional period of over-watering.

University of Maryland Self-Watering Container: