Summer Lawn Management: Watering the Lawn

How much water does my lawn need?

This varies somewhat depending on grass type. In general, applying one inch of water per week is the recommendation when there is insufficient rainfall during the summer drought.

An inch of water can be measured by marking the side of a tuna or pet food can placed on the lawn. **Remember that if nature provides water by rainfall, irrigation may not be needed. Nothing is more wasteful (and sure to attract attention for all the wrong reasons) than seeing irrigation running in the rain! Pay attention to current weather conditions and forecasts in order to use water more responsibly.

Tips for better watering

• Deep and infrequent watering maintains a healthy root system and reduces weed infestation (as opposed to light and frequent irrigation, which promotes shallow roots and germination of weed seeds).
• Applying one inch of water is often difficult to achieve in a single watering given the slow infiltration rate on most Virginia soils. Therefore, smaller amounts of water applied every four to five days may be required to allow water to enter the soil without causing runoff.
• Water is best applied early in the day (5:00 to 10:00 a.m.) when evaporation loss is lowest. Afternoon watering is acceptable but wind may affect uniformity. Night watering minimizes evaporation but may increase fungal diseases.
• Water the lawn, not driveways, sidewalks, or roads, by adjusting sprinkler heads.
• Mow your grass at the right height during the summer. Longer grass blades increase the depth of the root system, shade the soil, and help drought tolerance (see the following table).
• Learn to set your own control box.  There is no one-time setting for the entire year!  An irrigation system is a great tool for maintaining a healthy lawn but must be managed according to ongoing and changing seasonal conditions.  When in doubt – Less Is More!
• Set for infrequent watering days.  During very hot & dry conditions when your lawn starts to show extreme fatigue, manually override your system and give it an extra day of watering and then let system resume normal infrequent pre-set programmed days.  This will train your roots to chase deep into the ground searching for water making them much more mature and naturally drought resistant.
• Seeing your fescue lawn stress during the hottest 6 weeks or so during the summer is normal for our climate zone here in Central Virginia.

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