During May and June, garden plants will use about one inch of water each week. In July, August, and September, they require about two inches of water per week for best growth. It normally takes this amount of watering per week to maintain production if no rain falls.

One way of determining when to irrigate is to take a soil core sample from the plant root zone and squeeze it into a ball. If the ball holds together in the palm of your hand, the soil has sufficient water. If it crumbles, water can be applied.

At the crumble-stage, the average soil will hold an inch of water per foot. If this water is to be applied with a sprinkler, its delivery should be determined by placing three or four cans under the sprinkler pattern to see how long it takes to accumulate an inch of water.

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