When weed control is applied, the herbicide must be absorbed by the plant and move through the root system to do it's work. Weed control is most effective when weeds are taking in large amounts of food and water to their roots. Again, weed re-growth from rootstock may occur. For those of you who have sprinkler systems , don't get too anxious to turn on those systems. Late hard frosts in April can cause damage to exposed sprinkler system components.
Lawn watering requirements change throughout the growing season.
If we experience two to three weeks in the spring without moisture, hand watering your lawn is recommended. As we move into summer most of us set up a regular schedule for watering. Watering each area of the lawn for 20 - 30 minutes every third day may be adequate during some times of the year, but this type of structured program does not fit all conditions. The summer of 2000, for example, was extremely hot and dry and lawns required more water. If on the other hand the summer season is rainy, you can reduce your watering and conserve water.