An expanse of carpet-like green, cooling and soft to the feet, is definately a wonderful thing. However, the lawn is the highest maintenance plant we grow in Calgary. It requires more water than our climate normally provides, needs to be cut weekly (and the cuttings disposed of), and diligent weed monitoring is a must. Here are some water wise and responsible gardening tips for growing a healthy lawn in Calgary.
To stay healthy, your lawn only needs 1" (2.5 cm) of water per week. The City of Calgary is currently running commercials recommending using a frisbee to measure the water. Watering the recommended amount encourages the development of a deep root system which makes the lawn stronger and better equipped to handle the dry summers.
Water your lawn in the morning when it is not as hot and the wind is low. This reduces moisture loss due to evaporation. Set your sprinkler to water only the area that needs water.
Avoid setting irrigation systems on automatic timers. If it has already rained 1" during the week, the lawn does not need to be watered.
Most lawns in Calgary have a high percentage of Kentucky Blue grass in them. This is a cool weather grass which naturally goes into dormancy when the temperature rises above 24o C and there is insufficient water. Although the lawn tends to brown during the hotter months of the season, this is a period of dormancy only, the grass will green up again when the weather cools down.
Keep your mower blades sharp and set to 3" (7.5cm) in height. Longer blades help shade the root system, again reducing moisture loss and sun/heat damage. Cut the grass when dry and the clippings can be left as a natural fertilizer, returning soil nutrients and helping keep weeds away and moisture in.
Healthy and longer lawn grass is less susceptible to weeds, as the weeds are not able to compete. Use a fork weeder to dig up dandelions, getting all or as much of the root as possible. Don't let dandelions, or any weeds, go to seed. Quack grass is the same family as your lawn grass, and broadleaf weedkillers (eg: Killex) will not work on it and a non-selective weedkiller (eg: Roundup) will kill the lawn grass as well. Proper watering and allowing the lawn to dry out will help control quack grass as the root system is shallower and it will suffer from drought sooner. Actually painting the quack grass with Roundup works, but takes a lot of diligence and patience. If your lawn is very unhealthy and weed infested, you may want to contact an environmentally responsible professional to help.
Aerating is best done in the fall. The soil plugs will then have time to break down before the first mowing of the following spring.
Fertilizers and Pesticides
By following the tips above your lawn will be naturally healthy. Top dressing with compost is a great natural fertilizer, and there are companies in Calgary that specialize in organic lawn maintenance. Keep in mind that chemical fertilizers and pesticides are washed into our storm water system and return to the river untreated.
Lawn or not?
If the only time you walk on your lawn is to mow it, you may want to think about reducing the lawn area. Increase the size of your shrub and flower beds, and consider using some drought tolerant groundcovers instead.