Autumn is an ideal time to examine the lawn for summer wear and tear, and carrying out work in September will allow the grass to respond to treatment before soil temperatures fall too low.
Scarifying
‘Thatch’ (old grass stems, dead moss and other debris) can build-up on lawns
between grass roots and foliage. Regular raking (left) keeps
levels at an acceptable level, but a layer greater than 1cm
(0.5in) can impede water and fertiliser penetration. To remove
such build-up rake vigorously but carefully with a spring-tine
rake - a process known as scarifying. For larger areas powered tools are available as single
units or mower attachments.
Turf is damaged if scarified too deeply. Do not scarify in spring - opt instead for a light raking.
Aerating
Compacted lawns benefit from spiking to deter summer drought
and winter waterlogging. For an average lawn aeration every
two to three years should be adequate. Concentrate on areas
that receive the most wear.
Small areas can be spiked with a garden fork (see photograph above right), spacing holes 10-15cm (4-6in) apart. On clay or waterlogged soils use a hollow-tine aerator (see photograph above left) every three to four years. This extracts plugs of soil from the lawn. After hollow-tining sweep up the plugs then top-dress with a sandy mixture to improve air and moisture penetration.
Top dressing
Top dressing corrects surface irregularities and improves
the texture of difficult soils, consequently encouraging greater
rooting and thickening of turf. A simple mixture is three
parts sandy loam, six parts sharp sand and one part compost
or leafmould (by volume). Apply 2-3kg per sq m, working the
dressing in well with the back of a rake.
Flattening
To correct bumps and troughs, use an edging iron to slice through turf and roll it back. Fork over, adding or removing soil as needed. Replace the turf, and water thoroughly.
Further information
The above photographs are reproduced by kind permission of Dorling Kindersley and are taken from the RHS Practical Guide to Lawns and Ground Cover. Price £4.99. Buy online at dk.com