Many residential lawns look terrible during the summer heat and need to be permanently sustained with a whole range of chemicals. They have a nasty tendency to yellow in summer, and dandelions and many other weeds quickly invade them. What can be done?
In fact, most of these lawns suffer mostly from malnutrition and compaction. Add to this acid rain and an unusually dry summer, and the lone survivors will be the dandelions or other tough weeds that can tolerate such conditions. The ecological management of a lawn is mainly a matter of common sense: the problems need to be dealt with at the source, and the laws of nature need to be respected to avoid having to engage in a constant battle. After that, everything is simple.
Imagine an individual suffering from a chronic backache who would treat it with aspirin, but who does not modify his lifestyle at all. Such a treatment would be repetitive and would not deal with the cause of the problem. This is what is done to many lawns: they are laid on poor dirt, cut down to 5 cm and overfed with chemicals, which will promote a superficial root system and attract parasites.
To obtain a beautiful lawn, without using chemicals, this is what is needed:
A well-prepared soil.
It is essential to start with a good soil so that the turfgrass develops a deep root system and can prosper over many years. Therefore, it is necessary to know your soil and how it can be improved, if needed. Before the turf can be laid, the soil will have to be loosened to a depth of 15 to 20 cm; it should contain organic matters and the minerals essential to good growth. Have the soil tested (at a garden center) before installing the turf and follow the recommendations given by someone who has had training in horticulture. If the lawn is already established, you can improve its condition little by little by spreading a fine layer of compost on the surface, every year, in the spring and the fall.
The appropriate type of seed for the location.
Most lawns consist of plants that love the sun (bluegrass, ryegrass) but that also need a good shower, on a regular basis. If you have shady spots, sow types that tolerate shade better (fescue). There are also types that tolerate drought better (clover, fescue) and can withstand treading better (tall fescue, ryegrass). If the conditions are too severe for the lawn, consider installing a ground cover. There is a wide choice available for shady areas (periwinkle, pachysandra, ajuga, etc.) as well as for areas exposed to full sunlight (trefoil, creeping thyme, wild thyme, creeping juniper, etc.)
Some regular or seasonal care will keep your lawn dense and neat. The most important one is the mowing: by mowing your lawn at the height of 8 cm (3 inches) it will be much more resistant to drought, and you will eliminate a significant number of weeds since they will not be able to germinate in the shade of tall grass. Leave the cut grass on the ground; this will favor decomposing organisms that aerate your lawn, and it will also replace part of the fertilizers.
Soil aeration is another significant point because our lawns are subjected to intense treading. Once a year, rent a mechanical aerator to aerate your lawn. However, a manual tool can also do the trick for a small yard.
Then, check the pH of your soil; it should normally be between 6 and 7 (a soil pH analysis will cost you about $5 at most garden centers). If the pH is too low, all that is needed is a little lime that can be added by following the instructions provided on the bag.
Finally, use 100% natural fertilizers that will give density to your lawn. Natural fertilizers are a little bit more expensive than the chemical ones, but on the other hand, only one yearly application is required because they are not soluble (and they do not pollute the waterways either). Furthermore, you can lessen the quantity indicated on the bag by 30% if you leave the cuttings on the ground. If you used compost, you could still decrease the volume by another 30% and, if you have clover… take a good look at your lawn and see if you need fertilizers at all!
Accept diversity as an integral part of a healthy environment.
A lawn is not an artificial carpet. It is an area that is alive and which contains a lot of harmless, or even beneficial, organisms. These may be plants, insects or earthworms. Be tolerant towards nature. Add clover when you reseed your lawn in the spring; it will give your garden a new “look” and will make other large-leafed plants much more acceptable!
Understand that infestations are not symptoms of an underlying problem.
It is not advisable to apply pesticides (even natural ones) repetitively to solve an infestation problem. It is better to correct it at the source, even if it means replacing the whole lawn with a landscaping design that is more appropriate to the conditions. The best weapons against infestations are prevention, a good maintenance program, and a diversified environment, where the competition among the different organisms prevents anyone of them from taking over.