Water Wise Landscaping

Within the last year, southern New England gardens have gone from very dry to very wet. Both weather conditions can have an adverse effect on your lawn and landscape. An environmentally friendly home landscape can reduce your overall use of water and save you money. Dick Perreault, URI Master Gardener, created a landscape that is both beautiful and environmentally friendly. We visited his home to learn about watering wisely.

When to water and how much to water are the two key questions. While most gardeners worry about drought, over-watering can be an even more serious problem. The summer of 2003 has been very wet so Dick has only watered his lawn 4 or 5 times. Not only does it look great, but his water bill is much lower.

How much water does your lawn need?

Rule of Thumb: only about 1 inch of water per week is generally required to wet soils to a depth of about 4-6 inches, (ideal for plant growth). If it has rained 1 inch or more in a week, there is no need for supplemental irrigation. Save yourself time and money by not turning on the sprinkler during a wet period. If you don't have the luxury of automatic sprinklers, consider letting your lawn go dormant in the summer. It will brown but the grass will revive and green up in the fall.

How do you measure how much rain has fallen?

Use a rain gauge in your garden or lawn to measure the amount of rainfall. To check soil moisture, use a garden spade to examine the soil to a depth of about 6 inches. If the soil appears dry, it is time to water.

How do you know how much water your sprinkler puts out?

Place a tuna fish or cat food can in the vicinity of the sprinkler in your garden or lawn. Using a ruler, measure the amount of water in the can. Natural rainfall plus sprinkler output should not exceed 1 inch per week.

Wise Watering Tips

  • it is best to water early in the morning to avoid evaporation
  • watering deeply encourages deep healthy roots; deep roots means the lawn will be more tolerant to dry spells in the future
  • watering lightly is counterproductive and encourages shallower roots
  • many sprinklers apply water faster than the soil can absorb; consider dividing your watering into two or three periods to make sure the ground can absorb the water

Automatic Sprinkler System Tips

  • Goal: to apply water evenly, avoiding runoff and overspraying
  • Divide your lawn into zones and monitor rainfall and sprinkler output in each zone
  • Check and adjust sprinkler heads seasonally
  • Adjust watering schedule to reflect the seasons. For example, you will need to water less in the spring than in the autumn.

If you have an automatic sprinkler system but are unsure of how to operate it here are some ideas of where to get help:

  • refer back to the manual
  • identify the manufacturer, find them on the internet for further directions, or call them for answers to your questions
  • call the person/people who installed your system for advice

In areas of your home landscape where there is unhealthy lawn, consider replacing it with drought tolerant shrubs and trees. These plants do not require supplemental water once established. Lawns require 7-10 times more water to maintain than from all indoor uses. Reducing the amount of lawn by even just a small amount can make a big difference.

For more information please call the URI Master Gardener's at 1-800-448-1011.

Plant Pro Tips written by Rosie Lalli, Coastal Fellow