Lawn watering and soil type
In the summer months, there is an increase in the demand for water. Keep your lawn green and garden growing by using more efficient watering practices.
Outdoor water tips:
- Water your lawn in the cool part of the day, either early morning or early evening.
- Raise the blade level of your lawn mower to six to nine centimetres.
- Give your grass 1½ to 3 centimetres of water once per week.
- Frequent watering encourages shallow root growth and unhealthy grass.
- Don't apply fertilizer (nitrogen) in the summer - new growth requires more water.
- Sweep sidewalks and driveways clean instead of using a running hose.
- Avoid puddles and runoff when watering your lawn.
- Save water by xeriscaping.
- Use a trigger nozzle on your hose.
- Buy an outdoor water kit and save!!!
- Repair all leaks, change a washer!
- Plant drought-resistant trees and plants.
- Place a layer of mulch around tress and plants to slow the evaporation of moisture and discourage weed growth.
When lawn watering, it's important to know the kind of soil your lawn has. Soil type affects water absorption and the soil's maximum water holding capacity. Therefore, different soil types need different watering amounts. Follow these easy steps to perfect lawn watering:
- examine soil and select soil type
- measure the depth of grass roots
- use chart (below) to find lawn's water- ing amount
- do 'catch-can test' to find sprinkler run time
- water off-peak and learn to recognize signs of drought
Determine soil type
Soil is made up of sand, silt and clay particles. Your soil's mixture of these particles determines its soil type or its texture. It's rare to find only a sand or clay soil. You can figure out your soil type by using the chart below, or have it professionally analyzed. Call Toronto's Civic Garden Centre at 397-1345 or the Soil and Nutrient Lab, University of Guelph, at (519) 767-6226.
|Sandy Loam||Individual sand grains can readily be seen and felt. Squeezed when dry, a cast can be formed which readily falls apart. Squeezed when moist, a cast can be formed that will bear careful handling without breaking.|
|Loam||A somewhat gritty feel, when moist is slightly plastic. Squeezed when dry, it will form a cast that will bear careful handling, the cast formed by squeezing the moist soil can be handled quite freely without breaking.|
|Silt Loam||When dry, it may appear quite lumpy, but the lumps can be readily broken; and when pulverized, it feels smooth, soft, and floury. Either dry or moist, it will form casts that can be freely handled without breaking; but when moistened and squeezed between the thumb and finger,it will not "ribbon" but will be broken in appearance.|
|Clay Loam||When dry, usually breaks into lumps that are hard. When the moist soil is pinched between the thumb and finger, it will form a thin "ribbon" which will break readily. The moist soil will form a cast that will bear much handling. It does not crumble readily.|
Soil Cast = clump created by squeezing a small amount of soil in the palm of your hand.
Root zone depth
Dig out a chunk of grass and use a ruler to measure how deep the roots are growing. The depth of your grass' roots is important when deciding how much water your lawn needs each time you water. Together, the root zone depth and soil type determine the correct amount of water for your lawn. Example: A 20 cm root zone depth and sandy loam soil type needs 2.6 cm watering amount.
|Root Zone Depth||Sandy Loam||Loam||Silt Loam||Clay Loam|
Note: Watering amounts are average values and may vary slightly depending on exact soil type and root zone depth. At the first sign of run-off or puddles, reduce water amount.
Sprinkler run time
To find out how long to water your lawn to reach its required watering amount, perform a "catch can test".
If you water with a portable sprinkler, place identical-sized, straight-edged containers in a straight line leading away from the sprinkler to the edge of the sprinklers' water pattern. If you water with an in-ground irrigation system, place identical-sized containers randomly throughout your lawn's irrigated area.
- Run sprinkler for 15 minutes.
- Measure the depth of water in each container.
- Add the depths together. Divide by the number of containers.
- The result is the average amount of water delivered by your sprinkler in 15 minutes.
Example: You used four containers and they collected two, three, three and four cm of water. Therefore, your sprinkler is delivering 3 cm of water in a 15 minute period.
How often to water
If you have an automatic timer attached to your outdoor water tap, set your sprinkler to water late at night, just before you go to bed or early in the morning, just before you go to work. The best time is during "off peak" times, between 11:00 p.m. and 8:00 a.m. The great thing about this is that you don't have to worry about turning off your tap, it will turn off automatically. Remember, if the weather forecast is calling for rain, leave the watering to nature!
Do you need to water?
- Walk on your grass, does it spring back into position or do your footprints linger for awhile? If your prints linger, get out the sprinkler.
- Is your grass a bluish-green rather than a bright green? If yes, you may need to water.
- Are your roots getting enough moisture? Insert a moisture probe (the ones you use for house plants) deep into your lawn to monitor its moisture level.
- Seeing puddles and run-off from your lawn? Don't touch the sprinkler, your lawn needs a break. Let your lawn dry out between waterings to discourage fungus and rot.
Other helpful resources
For more information related to natural lawn and garden care, please go to www.toronto.ca/health/pesticides/index.htm
Get a great lawn with all the trimmings: Your guide to lawn care
- Xeriscaping: water-conserving landscaping
- Organic lawn care
- Organic insecticides and fungicides for the garden
- Natural recipes for a pest-free garden
- Using plants to protect other plants
- Grass seeding tips
- Alternative groundcovers
- Gardening - make the mulch of it!