Then apply a light overall dressing of sandy loam soil working this well into the crevices between the turves with the back of a rake. This will also help to correct minor differences in levels. When the grass resumes growth in spring lightly top at the first mowing, then adopt the routine treatment for established lawns but, if possible, leave until early summer, when the turves should be well rooted in, before I subjecting it to regular use. LAWN MAINTENANCE FEEDING Regular feeding is an important aspect of lawn maintenance. It encourages vigour and density in the turf, giving more resistance to disease, drought, hard wear and invasive weeds and moss. Spring A single dressing in early spring of a compound fertiliser containing nitrogen, phosphate and potash will supply most of a lawn's seasonal nutrient requirements. Apply in mild, showery settled weather as the grass is beginning to grow freely-in southern Britain usually towards the end of March; in northerly regions early to mid-April. If weather conditions are unsuitable delay application for two or three weeks. The simplest approach to feeding is to use a proprietary turf fertiliser formulated for spring and summer use. The analytical content of different brands may vary considerably. An analysis of 5 to 7 per cent nitrogen, 10 to | 15 per cent phosphoric acid and 2 to 4 per cent potash provides a good and economical balance of nutrients. Alternatively a simple, quick-acting spring lawn feed can be made up from: 35 parts by weight sulphate of ammonia, 60 parts by weight superphosphate and 5 parts by weight sulphate of potash, applied at 20Z. per square yard (55 g per m2). Although such mixtures will usually provide sufficient phosphate and potash to meet the season's requirements, vigour will decline as the season advances and nitrogen becomes depleted. To counteract apply sulphate of ammonia two or three times during the season, as necessary, at the rate of \ to Joz per square yard (7 to i4g per m2). It is safer to mix this with 3 to 40Z (85 to nog) per square yard of sandy soil before application to ensure more even distribution and to guard against the risk of scorch. Apply in cool, moist conditions, not during hot, dry periods. Alternatively, add slow-acting nitrogenous fertilisers to the spring lawn dressing to extend the period of nitrogen release, e.g.: 15 parts by weight sulphate of ammonia, 15 parts by weight dried blood, 40 parts by weight fine bone meal, 25 parts by weight superphosphate and 5 parts by weight sulphate of potash, applied at 20Z per square yard (55g per m2). Poor colour in turf can often be strengthened by adding calcined sulphate of iron to the spring dressing at the rate of joz per square yard (5g per m2). Use in moderation; excessive amounts can cause deterioration of the turf. AUTUMN If a lawn has suffered from summer drought or heavy compaction, an autumn fertiliser dressing will aid recovery. It should contain a good level of potash and phosphate to encourage healthy roots but should be low in nitrogen, e.