Lawn Care: Lawn Mowers and Thatch

It's a paradox that the more carefully a lawn is nurtured, the more likely it is do develop thatch. Thatch is an elastic layer of stem and grass residues and all lawns have it to a certain extent. When it is more than a inch deep it becomes a problem for the lawn for several reasons: it can harbour diseases and insects, it can impede watering and weed control and it can interfere with lawn mower operation.

Thatch accumulates most often on grasses that have been heavily fertilised in the past and should be removed by hiring a specialist mower designed for dethatching - these mowers have vertical rather than horizontal blades and they slice through the thatch and draw it to the surface. It should then be drawn off the lawn with a rake. If you prefer to dethatch by hand, you should use a strong rake and dethatch the lawn once a week for at least a month, without cutting the grass during this period.

It's important to leave a lawn alone for at least a month after dethatching to re-establish its grown pattern and to allow the stems at ground level, which will have become weak through being compressed by thatch, to thicken and toughen before being cut again.

The best time to carry out dethatching is about a month after the first cut of the year. Don't try to dethatch after about the first week in September as the grass will be heading for dormancy and removing the insulating thatch that it has become used to could cause exposed areas of lawn to die back completely over the winter.

Although it cannot easily be seen, thatch can damage the appearance and health of your lawn. Dethatcher courtesy of www.gardening-tools-direct.co.uk