Along with these tips, please remember that the city's lawn watering policy is in effect year-round.
When to Water
- After 10 a.m., heat and evaporation increase and remove the moisture resulting in less effective watering and wasted effort. Watering at night is not recommended because the lawn stays wet for a longer period which can promote diseases and affect the health of your lawn. Remember, lawn watering is not allowed in Woodbury between noon and 5 p.m. every day, even if it is “your day” to water.
- Water only when your lawn needs it, rather than on a set schedule. Here are some helpful tests to see if your grass needs more water:
Color – when water is not available for an extended period, the lawn will have a bluish-gray cast.
Foot printing – walk across the lawn and if the stepped-on grass does not stand up right away, or is still visible after 30 seconds, it’s time to water.
Leaf check – during dry periods, grass responds by wilting, rolling, or folding.
- Water deeply and infrequently – watering once or twice a week with a good soaking is usually enough to keep a healthy lawn growing. The grass should be allowed to dry between watering which encourages deeper roots. Over-watering grass promotes shallower roots which are less drought-resistant and more prone to winter kill.
- In general, your lawn needs about 1 inch of water per week, including rainfall, to keep it green during the growing season. Purchase a rain gauge to allow for easy rainfall measurements.
- Adjust lawn watering to the weather. Following a heavy rain, skip your regular watering day until the grass needs it again according to the amount of rain that fell.
- Delay regular lawn watering during the first cool weeks of spring and in late fall. This encourages deeper roots and makes your lawn healthier.
Managing Irrigation Systems
- Install rain or moisture sensor technology if you have an automatic irrigation system (it is required by state law).
- Teach all household members how to turn off an automatic irrigation system when its use is not necessary.
- Consider installation of a “smart” irrigation control system which when properly installed and maintained can automatically adjust watering frequency and amounts based on weather and site conditions.
- If you have an automatic irrigation system, check the heads periodically. Be sure they haven’t shifted direction to spray water on the side of the house, driveway, or sidewalk instead of the lawn.
- Grassy areas on sunny southern sides of buildings or on slopes and areas near sidewalks and driveways may need to be watered more often. Shady areas and northern exposures need water less frequently. Have your irrigation contractor complete an assessment on your irrigation system and adjust the irrigation zones accordingly.
Video funded in part by a grant from the Minnesota Pollution Control Agency
Selecting an Irrigation Vendor
When selecting an irrigation vendor to install or inspect your irrigation system, be sure that they are licensed, bonded, have appropriate plumbing and electrical qualifications, and carry one or more of the following credentials:
- Certified Irrigation Contractor (CIC)
- Certified Landscape Auditor (CLA)
- Certified Irrigation Designer (CID)
- Member of the Minnesota Irrigation Landscape Association (MILA)
Other Helpful Tips
- Mow grass to a height of 2 to 3 inches. Taller grass shades the roots and soil surface, which helps the amount of water lost to evaporation.
- Sprinklers and sprinkler heads that throw large drops in a flat pattern are much more effective than those with fine, high sprays, which can be blown about and evaporated quickly.
- Don’t water your lawn too much by forgetting about manual sprinklers. If you use manual sprinklers, buy timer attachments that hook on between the faucet and hose, or set a kitchen timer to ring in 15 or 20 minutes to remind you to move the sprinkler to a new area.
- Recycle water by using barrels to collect rain water from gutter downspouts and using this rain water to water landscape vegetation and indoor plants. You can order a rain barrel online at RecycleMinnesota.org.
- Not all soil is the same. If your grass grows on mostly clay soil, between ¼ and ½ inch of water per hour can be absorbed before it starts running off wastefully. If you have sandy soil, you’ll need to water more often and for shorter periods of time.
- Use root feeder or water-aerator probes around trees and bushes. Even for the biggest trees, you need go no deeper than 18 inches, while 8 to 12 inches is plenty deep for smaller trees and shrubs. The probes get water precisely where it’s needed and simultaneously create lots of little holes that provide aeration benefits.
- If you're thinking about planting a garden, wait until there is rain in the forecast to decrease the need for additional water. This will save time and money and will increase the survival of your new plants.