Lawn Watering Guide

The type and slope of the soil, the fertilizer used, the amount of water needed by specific plants and grass and the efficiency of sprinklers all affect how often one needs to water.

Soil Type
Lawns on sandy soil require more frequent watering than lawns or loam or clay soils. Water can be applied less often to clay and loam soils, but it should be applied more slowly to prevent runoff.

Slope
To avoid runoff on sloping areas, place sprinklers near the top of the slope. Apply water slowly for 5-15 minutes, turn off for 15 minutes, on 5-15 minutes, etc. until the correct amount of water has been applied.

Fertilizer
Applying fertilizer to the lawn at the proper time and in the proper amount can save time, effort and money through reduced mowing and watering. Fertilizers also can be a major source of pollution of streams and groundwater if excessive amounts are applied.

The best way to determine whether your lawn requires additional plant nutrients is to have the soil tested. A soil test report will help you understand which nutrients your soil lacks and which are present in adequate amounts. The test results will include recommendations on the amounts of plant nutrients that would benefit your lawn. Soil tests are easy and inexpensive. Forms and instructions are available through the county extension office or on the Texas A&M Soil Testing Laboratory's website.

To grow properly, all plants need essential nutrients. Those that are typically needed in the greatest amounts are nitrogen, phosphorus and potassium. The best fertilizer for your lawn is one that contains the ratio of these three nutrients needed as indicated by your soil test results. All fertilizer packages must list three numbers (such as 15-5-10).

These numbers-known as the fertilizer analysis-represent the percentage by weight of nitrogen, phosphorus, and potassium in the fertilizer. Most soils in this area already have enough phosphorus and potassium. If the soil test indicates your lawn does not need phosphorus and/or potassium, choose a fertilizer that provides only nitrogen.

Learn more on how to fertilize for warm season grasses

Trees, Shrubs & Groundcover
Established plantings do well in the summer when watered about once a week, especially if mulch is placed around plants. Apply enough water to wet the soil to a depth of at least 12 inches. Using low output sprinkler heads, bubblers, or drip irrigation systems help prevent runoff and are efficient ways to apply water. New plantings require more frequent watering the first two years. Consider Texas native, Water-Wise varieties when purchasing new or replacement plants

How to Water Your Lawn
  • Water your lawn or landscape early in the morning (before 10 am) or late in the afternoon (after 6 pm) to avoid loosing water to evaporation.
  • Do not over water your lawn. Texas soils can only absorb so much moisture and the rest runs off, wasting water. Watering using the "cycle soak" method is the best way to get water deep in to the root zone and avoid runoff and water waste.  Also, during winter months reduce your watering frequency to once every 15 to 20 days.
  • Water only when needed. If it rains, you do not have to water your lawn. To better track rainfall, buy a rain gauge.
For more information:  Outdoor Watering