Adequate moisture, a porous soil, regular mowing, and
sufficient nutrient levels are the basic requirements for growing a
fine lawn. To ensure great results though, there remain a few things
that should be done, and one or two that are not appropriate for lawn
care during the summer.
On condition that the grass is growing
vitally and looking green and healthy, professional lawn care involves
filling out the dips and small depressions in the lawn, with either
sand, or a mixture of sand and compost, known as top-dressing. Not only
is this an excellent way of straightening out the grass, but the
treated spots react very positively to the treatment, and tend to cover
with grass in a couple of weeks or so. Please note that the sand must
be thoroughly leached of salts. Light, sandy soil, well mixed with
compost, can be used as an alternative.
The height at which the
top-dressing can be spread differs according to the type of lawn.
Grasses that grow from seed, such as the Fescues, should be treated
gingerly, with only a thin layer being spread at any time. Some
warm-climate perennial grasses, like Buffalo or St. Augustine, should
not be smothered either. The tips of the grass blades should be visible
through the sand. Therefore, when a relatively deep pit needs
straightening, the job has to be carried out in stages, the
top-dressing only being repeated, when the grass is clearly growing
well through the initial layer.
Other perennial grasses, like
Bermuda, Kikuyu and Zoysia varieties, grow by means of underground
stems, known as rhizomes, which allow the species to recover from
neglect, and also from being covered with a layer of sand, for a brief
period of time. In fact, it is possible to spread the top-dressing
mixture to a level of up to 10cm, (4in) providing of course that the
grass is active and clearly growing strongly. It follows therefore,
that this task should not be attempted during the lawn's dormant
season, or if it is in poor shape and growing weakly.
In such
cases, the lawn needs rejuvenating before the top-dressing treatment is
attempted. Other than insufficient moisture, an inadequate mowing
regime, and possibly nutrient deficiency in the soil, soil compaction
is usually the main reason for a poorly performing lawn. Compaction at
the topsoil level can be relieved by a scarifying machine, (the tool
with which de-thatching is carried out in the spring) while at deeper
soil levels, an aerating instrument may have to be employed. Following
these tasks, slow release fertilizer should be applied.
When
maintaining a healthy lawn however, it is preferable not to fertilize
during the summer, as excessive nitrogen levels encourage fungal
infections, and unnecessarily, rampant growth. Feeding is best carried
out in the spring and autumn, ideally with either slow release
fertilizer, or an organic amendment.