In general, fescue turf grasses need about 3/4″ – 1″ of water per week to maintain a nice green color and active growth. However, during certain times of the summer when high temperatures are the norm, you should allow lawns to naturally slow down in growth. You may even let the lawn go almost completely dormant in hot weather. There are a lot of factors that impact your lawn’s water needs, including soil and weather. Here are a few guidelines we have found get great results.
- Decide beforehand. Decide before the summer heat arrives to either water lawns consistently as needed throughout the season, or let lawns go dormant as conditions turn hot and dry. Do not rotate back-and-forth. In other words, don’t let the grass turn totally brown, then apply enough water to green it up, then let the grass go dormant again. Interrupting the lawn’s dormancy actually drains large amounts of food reserves from the plant.
- When is it time to water? The first few warm days of summer do not automatically mean it’s time to water lawns. In fact, allowing lawns to start to go under mild drought stress actually increases rooting. Watch for “foot printing,” or footprints remaining on the lawn after walking across it (instead of leaf blades bouncing back up). Grasses also tend to turn darker in color as they go under drought stress. Sampling the root zone of your soil is another option.
- Water as infrequently as possible. Thoroughly water when you do water, so moisture soaks down to the roots. Exceptions to this general rule are for newly seeded lawns where the surface needs to stay moist, and newly sodded lawns that have not yet rooted into the soil. Otherwise, avoid frequent watering, which promote shallower root systems and weeds (e.g., crabgrass). It is better to water for longer periods of time than more often. For example, 25 minutes three times a week is better than 15 minutes five times a week. A good rule of thumb is to water three to four times a week, watching to weather and adjusting as needed.
- Water early in the day if possible. Given a choice, water early in the day when lawns are normally wet from dew. Avoid midday watering due to excessive evaporation, and at night due to potential increases in disease.
- Water conservation. To help conserve water, mow your lawn at a higher than normal height, avoid applying an excess of nitrogen as warm weather approaches, limit traffic over the lawn, improve turf rooting, control thatch and soil compaction, and avoid pesticide use on drought-stressed lawns. Don’t allow water to hit the driveway or the street.
- Avoid over-watering. Use a rain gauge to measure how much water you’re applying. Over-watering does more than deplete the water supply, it also makes plants prone to pests and adds to stormwater runoff, which pollutes our water systems. By choosing and operating a watering system correctly, you can reduce water bills, insect and disease problems, and maintenance requirements. The more you water your lawn, the faster it grows and the more it needs to be mowed.
- Monitor rainfall. Don’t water the lawn if rains are expected soon. Keep track of rainfall for the week and don’t apply any more water to the lawn than what is absolutely necessary. The guide of about one inch of water per week is only a guide. If your lawn doesn’t get that one inch of water, it’s not going to die.
Below are examples of Brown Patch, a fungus which can be caused by afternoon watering. Contrast that with the great looking Basnight Land & Lawn property pictured above, and give us a call if you have questions about your property and proper irrigation.