Submitted by Calvin Finch, Ph.D., Manager, Conservation Division, Water Resources & Conservation Department, SAWS, and Horticulturist

WAIT TO FERTILIZE AND WATER THE LAWN

As the temperatures increase there is an inclination to start watering the lawn and to fertilize. Do not rush either practice or launch the practices with an over abundance of enthusiasm!

Wait on fertilization until you have mowed real grass twice. If you fertilize earlier than that, the nutrients are partially wasted. Until the soil warms and roots become active, the St. Augustine, zoysia, Bermuda, or buffalo roots can not take up the nitrogen. Nitrogen is active, so if the plant can not use it, the material volatizes into the air or leaches into the soil past the root system. If you have weeds in your lawn, the weeds will love the early fertilization. The best time to fertilize usually is the last week of April or first half of May.

The advertisements for “weed and feed” products have begun. If fertilizing early is a waste of nutrients, using “weed and feed” is a double waste of resources. “Weed and feed” products just do not work in the South. The best time for herbicides is in February and the best time for fertilizer is May. If you apply the product now you are trying to kill weeds that have already started to decline and, again, the fertilizer is too early. The weeds in place now are cool weather weeds. They are mature and going to seed. The hot weather will kill them before the herbicide.

Watering can also be a waste now. After about three weeks of warm weather the lawn is ready to start to green up. Water at that time may contribute to green up. Before the grass is ready, applying frequent irrigation only helps the weeds. When you do begin to irrigate, only water where the lawn really needs it. Start out with sprinkling every two weeks or, better yet, follow the ET recommendations on the front page of the “San Antonio Life” section of the Express-News. ET is a measure of actual water need. The recommendations are provided by lawn grass type. For more information on ET, Milbergers, Fanicks, and Rainbow Gardens (Thousand Oaks and Bandera locations) nurseries will have the ET kit available free on April 13. The kit contains gauges and instructions on how to determine how much water your irrigation system produces in a unit of time.

            For efficiency’s sake, it is also important that you have your irrigation system checked for leaks and worn out heads before the irrigation season.

All irrigators should also keep in mind that it is against the law in San Antonio to irrigate with spinklers between 10 a.m. and 8 p.m. Wasting water is also against the law. Letting water run off your yard into the street or storm drain is considered water waste.

Water waste is reported to the SAWS emergency number at 227-6143. A SAWS customer service representative visits the site after the first complaint to alert the customer about efficient irrigation practices. After the second complaint, a water waster would be placed on the “water waster list.” The “list” determines who receives attention from SAWS Conservation Enforcement Officers. If they witness a violation they write a misdemeanor citation which requires that the responsible party must go to court. Fines for the first violation are $50 to $200, the second violation merits $250 to $500, and the third $1000 to $2000.

SAWS is not interested in giving out tickets. The best situation is if we all follow the watering rules and only water when the plants require it.