Successfully maintaining a lawn to a high standard requires performing the regular tasks correctly, and ensuring that certain special tasks are carried out on time.
In dry and hot summer climates, "regular tasks" would include irrigation, while in all climates, frequent mowing at the right height is also vital.
This article focuses on those tasks that need, specifically, to be carried out in the spring, and where failure to do is liable to result in less than satisfactory results.
*Removing thatch that has built-up over the previous year is one such special task.
Different lawn varieties produce thatch at varying rates.
In species like Zoysia, the mass of tough organic matter that takes ages to break down, just gets thicker and thicker unless removed.
If not, a layer is formed at the soil's surface that is impervious to some degree to water penetration and the exchange of gasses.
A host of problems arises as a result, including more pests and disease infestations, and a general degeneration of the lawn.
Thatch is ideally removed by a scarifying machine, which in addition to digging out the excess organic matter, scratches the soil surface, thereby relieving topsoil compaction and inducing new growth.
It can also be removed by mowing the grass as low as possible, an action that can have disastrous consequences for the lawn if performed at the wrong time.
Neither scarifying nor heavy scalping are appropriate for all lawn types.
Indeed, they can only be safely used on perennial grasses like Bermuda grass, Paspalum, Kikuyu, or Zoysia - species that develop perennating organs like rhizomes, within the soil.
*Top-dressing, in combination with dethatching and scarifying, is another technique employed by professionals.
Sand that has been leached of salts, is mixed with well-rotted compost or earthworm castings, and spread as a thin layer on the lawn.
With the lawn types mentioned above, as much as 5-10cm (1-2 inches) can be spread, but care must be taken with grasses like St Augustine or Buffalo that do not possess rhizomes and are shallow rooting.
The two great benefits associated with Top Dressing are that dips and hollows in the lawn are straightened out, while in general, growth that is more vibrant ensues.
Last ,but definitely not least, is feeding.
Shortly after the dethatching (assuming it is necessary) controlled release or organic fertilizer should be applied on the lawn.
The former need only be spread two or three times a year, and are arguably most effective in accelerating the break up of the organic matter ( usually stems and roots that decompose slowly) which form the thatch layer.
Controlled, or slow-release fertilizers may be considerably more expensive than readily soluble types like Urea or Ammonium Sulfate, but are far less damaging to the environment.