How much water does my lawn need?

This is a probably the most common question lawn care professionals are asked…  It is very easy to tell a client to “water each area of your lawn for 15 minutes per day”.  The truth is, this is a lazy answer and you could be over or under-watering your lawn.

The correct answer requires more information:

  • Does all your lawn have the same amount of sunlight exposure?
    • Lawns with full sunlight exposure will require more water than lawns that receive partial sun or are fully shaded.
    • Areas with a lot of shade MAY not require as much water.  This can be tricky:
      • Trees: If your shade is from a tree and there is a light storm, the water may not make it from the tree canopy to the soil. So in a situation like this, lawn that is covered by the tree may receive little or no water.  Now lets say you have an irrigation system and your zone waters an area under a tree. This area may require less water due to the sunlight not being able to penetrate the tree canopy to the soil, thus resulting in the area taking longer to dry. 
      • Structures: Lets say you have 2 homes that are built in close proximity to each other with a strip of grass between them. If the strip runs north to west, chances are the sunlight is only able to reach the lawn around noon. This is an area that may not need as much watering. If you have a strip that runs east to west, this could be a full sunlight area that could require more watering. 
  • What kind of Irrigation system are you using?
    • There are 3 main types of lawn watering most people use.
      • Watering the lawn with a hose by hand. Don’t do this as it is a waste of time and it is nearly impossible to get an even coverage.
      • Portable sprinklers are the sprinklers that hook up to a hose and need to be moved from area to area. If done properly these are completely fine. The problem is that is takes up a lot of the homeowners time to move the hose around the yard and is rarely done correctly.
      • Automatic irrigation system. These systems are installed by a professional. They consist of a control box, valve box(es), underground waterlines and pop-up sprinklers. There are 2 types of sprinklers customers use in an irrigation system; pop-up misters and gear driven heads.
        • Pop-up misters typically have a skinny middle section that pop-up about 4 inches from the soil.  The can spray in patterns from 1-360 degrees with a non moving/constant mist-fan like spray pattern.  They are typically used for small areas and typically cover distances less than 15 feet. Since pop-up misters do not spray long distances, the coverage area is hit with more water in a shorter amount of time. 
        • Gear driven heads are typically wider and longer than pop-up misters.  While they are typically about 8 inches in height, only about 4 inches rises above the soil.  They rotate from 0-360 degrees and spray more of a jet like spray pattern. These heads are designed to cover a larger area then the pop-up misters and can reach areas up to 50 feet.  Since the gear driven heads rotate and cover larger areas, it may take longer to get the same amount of water per square foot as a pop-up mister.
        • It is generally best to not have both gear driven sprinkler heads and pop-up misters on the same zone. Since pop-up heads spray more water per square foot per minute than gear driven heads, it could result in too much water in the pop-up coverage area or  too little water in the gear driven coverage area. 
  • What time of the year is it?
    • Here in Michigan, we tend to have a lot of precipitation in the spring.  If you see cool temperatures and rain in the forecast, you may be able to skip watering until the weather starts to warm and dry up.  You may be able to water for a shorter duration due to the cooler temperatures.
      • If you have an automatic system make sure you turn it on earlier than later to ensure the system is working properly. Many clients wait until it gets hot to turn their system on, only to find out that their system needs to be repaired.  Depending on the contractor, it could be a few weeks before the repair is done, resulting in a drought stress. 
      • Summer-early fall months are the most crucial for lawn watering. Don’t wait until your lawn has suffered from heat or drought stress as you could be fighting an uphill battle all year.  Make sure you begin watering before this happens. When temperatures get extreme, you may need to water more than once a day. It is more beneficial to water 2 times a day then watering for a longer duration once a day. 
    • What kind of soil do you have?
      • The ideal soil for a healthy lawn is topsoil.  The water gets absorbed by the soil and allows the nutrients to get into the roots of the turf.
      • Clay based lawns tend to have water sit on top of the clay as clay offers terrible drainage. Clay based lawns will need to be watered more frequently with less water than topsoil. Clay based lawns tend to have weaker root systems.
      • Sandy based soil will need to be watered for longer duration’s.  Since sand is very permeable, the water can just fall through the sandy soil, not allowing the water molecules to bind to the turf roots. 
    • Do you feel overwhelmed yet? Don’t be..
      • The truth is the most important thing to do when figuring a watering schedule is to look at your lawn on a regular basis. If you see your entire lawn is drying up, then increase watering duration. If you see only areas of a lawn that seems to begin drying up faster than others, then only increase watering in the areas that are drying up. In contrast, if you see an area of the lawn that seems always to be wet, reducing the watering duration in that area.
    • Last but not least…
      • Shorter more frequent watering is much more beneficial in the overall health of the lawn.  It is scientifically proven to reduce disease.  If your goal is to water an area of your lawn for a total of 105 minutes per week, break it up to 15 minutes per day. 

Ryan’s Watering Schedule

ZoneSprinkler TypeWater Overlap Coverage AreaSunlight ExposureDuration
1Gear DrivenHeavySmallSome Shade Mostly Sun10 Minutes
2Pop-up MisterHeavySmallSome Shade Mostly Sun10 Minutes
3PopupHeavySmall- Flower BedsMostly Shade5 Minutes
4Gear DrivenMediumMediumFull Sun15 Minutes
5Gear DrivenLightLargeFull Sun20 Minutes
6PopupMediumSmallFull Shade0 Minutes