Advice
RHS Help & Advice
Lawns from seed or turf
Time and preparation
Turf is best laid late September to late October; in mild spells continuing to late February. Seed can be sown in cool, moist conditions in early autumn or in mid-spring (mid-April to early May).
Dig or deeply rotavate the site, incorporating organic matter, preferably several weeks in advance to allow the soil to settle.
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Buying turf
Turf should be fresh, green, moist and weed free. Avoid turf that disintegrates when handled, is dull, yellowish or dry-edged. Lay with staggered joints closely butted, using sandy soil to adjust minor irregularities. Begin at one side (see pic 1 above), working forwards while standing on a board or plank (see pic 2 above). Gently firm after laying each turf or lightly roll afterwards.
Seeds
Select from high quality or general ornamental seeds, or harder-wearing utility (with ryegrass). Check the supplier’s recommended sowing rates. Prepare, level and firm as for turf. Rake in a light dressing of fertiliser. Sow by hand or distributor, half lengthways, half widthways (see left). Lightly rake in. In dry conditions water with a light sprinkler after two to three days, repeating until germinated and well established.
New lawns on badly drained clay
Lawns on heavy clay soils are prone to problems associated with poor drainage, including moss, weeds and lawn algae. One method to combat this is to sit the lawn on a layer of sand which draws water away from the surface. After preparing the soil, spread an 8cm (3in) layer of sharp sand over the top. Level and firm as necessary. This provides drainage and avoids drought stress by allowing the grass to root into the underlying soil. Some method of containing the sand is needed - brick, proprietary metal edging or timber. A week before sowing or turfing spread a 2cm (0.75in) layer of multipurpose compost over the area together with fertiliser and rake level.
Further information
Photographs reproduced with kind permission of Dorling Kindersley. Taken from the RHS Gardening Manual.