Lawn Maintenance – Keep your lawn healthy using good maintenance practices. Grow a healthy lawn by using correct fertilizing, liming, aeration, mowing, topdressing, over-seeding and irrigation practices.
Mowing – Mow high when it’s dry. Grass cut at a height of 6 to 8 cm (2 1/2 to 3 inches) will develop a deep, extensive root system and grow thicker. Grass this height helps the soil to retain its moisture better. Sharpen your mower blade in the spring and keep it sharp. Grass recovers more quickly and easily from a clean cut than when it gets torn from a ragged cut.
Leave the lawn clippings on your lawn after mowing. Lawn clippings compost, slowly releasing nitrogen for the grass. Under wet spring conditions, remove thick layers of clippings (over 0.5 cm thick) to avoid smothering your grass.
Watering – Water deeply and infrequently. Apply at least 2.5 cm (1 inch) of water (to help measure put a container on your lawn to measure how much you’ve watered it). Water when your lawn needs it rather than on a set schedule. Excessive watering can lead to poor growing conditions and disease problems. Consider the soil type and surface features. Grass growing on compacted, fine soil or on slopes requires more frequent light watering.
Early morning is the ideal time for watering. This minimizes water lost through evaporation and wind. Watering in the evening leaves the grass wet for longer, increasing the risk of disease. Grass growing near large trees may need to be watered more frequently because the tree roots absorb much of the soil’s water.
A healthy lawn can survive several weeks in a dormant state. In extended hot dry periods, a lawn may wilt, turn brown and become dormant. Common grass varieties like Kentucky bluegrass and fine fescues will turn green again when regular moisture conditions return. Check the lawn regularly to detect any pests or other problems early. It may be more difficult to detect or differentiate insect damage in a dormant lawn.
Fertilizing – Compost is a great fertilizer that supplies your lawn with nutrients needed for plant growth. Apply compost at any time in the season. Mix it into the soil before seeding or laying sod, or spread it in a thin layer raked over the existing lawn.
Commercial fertilizers usually contain the three major nutrients: nitrogen (N) to promote leaf growth, phosphorus (P) for root growth, and potassium (K) which is essential for stress resistance. The three numbers that manufactures put on the packaging represent the proportions of these nutrients, for example: 21-7-7 formulation contains 21% nitrogen, and 7% each of phosphorus and potassium.
Fertilizers with a slow-release form of nitrogen are preferred because they release nutrients uniformly and there is less risk that excess fertilizer will leach away from the root zone. All purpose turf fertilizers usually have an N-P-K ratio of 4-1-2. Rates and timing of fertilization can vary with the type of soil, the type of grass, and site and weather conditions. A lower rate is generally used in spring and early summer than in early and late fall. Organic fertilizers release more nutrients as the temperature and moisture levels increase, so you shouldn’t fertilize when conditions are likely to be hot or dry, usually from mid-June to early August. Combination products containing a herbicide and an fertilizer (weed and feed type) should only be considered if your lawn has a widespread weed problem and a nutrient deficiency.
Over-seeding and Replacing Sod – Most healthy lawns will recover from damage. Depending on the type of grass, vigorously growing lawns will fill in areas that have been thinned by insects or other types of damage. If bare patches do not fill in quickly, weeds may set in.
Over-seeding – Regularly spreading grass seed on your lawn will ensure that it remains dense. Over-seeding is best done in late summer to early fall. Topdressing with compost or topsoil can be done at the same time. Using the proper type of grass seed is very important for lawns in shady areas.
Replacing Sod – To replace sod: cut out the dead or damaged area to about 2 cm deep. Rake the soil and add some fertilizer. Lay down the new piece of sod. Step on it or roll it to ensure good contact with the soil. Keep the new seed and sod well-watered until the new grass is established.
Aerating – Aerating your lawn allows a better flow of water, air and vital nutrients to the plant roots, making it easier for them to grown. This does not, however, apply to soil types containing clay. Aeration is best done in late summer in conjunction with over-seeding and/or topdressing.
Signs that you need to aerate your lawn: 1) ground is hard and compacted; 2) thatch is building up; 3) water does not penetrate well; 4) weeds such as prostrate knot-weed and clover are present.
There are two types of mechanical aerators: solid-tined machines that drive spikes into the ground and core machines that removes small plugs of thatch and soil.
De-thatching – Thatch is a tough mixture of dead grass and roots that accumulates above the soil surface. In an healthy lawn, insects, earthworms, beneficial fungi and other microorganisms break down thatch and aerate the soil. Excessive watering, over fertilizing with nitrogen and heavy use of insecticides and fungicides may decrease the populations of soil organisms required to keep thatch levels down. Thatch that is more than 1 cm (1/2) thick can prevent water, air and nutrients from getting to the roots. Too much thatch can also harbour harmful insects and diseases. Remove excess thatch with a heavy rake or de-thatching equipment.