Gardening: How to use less water

Q. In my garden the past few years, I have had to water my vegetable plants quite often as they would wilt during the real hot months of summer. What can I do to cut down on the need for water?

— G. L. of Collinsville

A. Depending upon where you live in Collinsville, you can have a difficult problem with the use of water. The higher areas in the east are what you are describing. In the lower areas to the west near the American Bottom, you should have no problem at all as long as the Mississippi River aquifer can recharge a large amount of water.

Having water soak into the soil and not running off depends a lot on the amount of organic matter in the soil, the amount of decaying roots left in the soil from the previous year and how deep the roots grew. If the soil is left bare, it bakes, becomes hard and most of the rain runs off from higher areas to lower areas.

It has been demonstrated that if your soil has living plant material growing year around, the amount of water that soaks into the soil will increase. In three years, your soil can go from allowing 1/2 of an inch of rain to soak into the soil in an hour to as much as 8 inches per hour. If you remove the vegetable plants after they have stopped producing and replace them with a taller green ground cover in fall and allow it to grow over winter, this will break down the hard surface area and the rain will run down into the areas where the roots have penetrated deeper. Usually, the height of the plant above the ground indicates the length of the root penetration below the ground.

Some ground covers and cover crops to use:

* A groundbreaker mix of Austrian winter peas and groundhog cover crop radish which can be planted around Sept. 1 at the rate 1 pound per 1,000 square feet.

* Annual ryegrass planted six to eight weeks before the first killing frost (usually Oct. 15) at the rate of 1 pound per 1,000 square feet

* One receiving a lot of attention recently is Caliente 199 Mustard which is planted in September at the rate of 4 to 6 ounces per 1,000 square feet. You will need to cut this back in early spring just before it blooms. Wait about two weeks before planting any vegetables in the spring. This plant is related to the bright yellow mustard that we see every spring in our area. The Amish are using this in the central part of Ohio. They have also found this helps suppress weed growth and can prevent some plant diseases in the coming year.

Mulches, such as straw and newspaper, work well as they shade the soil and cool the soil. They also suppress weed growth. Some common weeds have some of the highest evaporation numbers as they lose water as the sunlight warms up the leaf structure.

If you do use water, apply 1 inch of water per week when you do not have a good rain. When enough of this water soaks deeper into the soil, the water does not evaporate and the roots grow longer and can withstand a drought.

Try to avoid an overhead sprinkler as they waste more water and you have to water early in the morning. Watering later in the afternoon can cause disease problems.