LAWN MAINTENANCE

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At this time of year, the lawn is actively growing and requires feeding, moss-killing, weeding and regular mowing. Spring is also a suitable time to over-seed sparse areas.

All lawns need feeding in order to maintain vigour. When feeding, look out for signs of pest or disease and apply moss killer if required. Regular maintenance is the best way to approach a lawn, and may avoid the need for renovation later on.

Over winter the lawn does not grow much, but once the weather warms up in early spring you can start mowing, and this is also a good time to over-seed any areas damaged over winter.

Mowing

This is the most obvious, and one of the most important, maintenance task over spring and summer. Mowing regularly keeps the lawn in good health. Cutting the grass fortnightly from mid-March until November (around 16 cuts a year) to maintain a healthy sward. 

Adjust the cutting height and mowing frequencies to match grass vigour and ground conditions. Lower the cutting height gradually during the spring until a cutting height of around 25 mm is reached. During periods of drought raise the height of the cut or postpone cutting to avoid stressing the lawn

Killing moss

Moss is a problem in damp, poorly drained lawns. Spring is a good time to remedy moss problems. There are several options for dealing with moss in lawns, either using cultivation or by chemical means.  

Remove loose moss in autumn, by scarification (vigorous raking). On small lawns this can be done by hand, raking out the moss with a spring-tine rake, but on larger lawns mechanical scarifiers can be hired.

For chemical control use a moss killer containing sulphate of iron in spring or early autumn. When the moss blackens after two or three weeks use a spring-tine rake to remove it. Apply mosskillers either by hand or with a push-along spreader. 

Be careful not to apply lawn sand (ferrous sulphate mixed with a carrier) at too high a rate as this can blacken and kill the grass as well as the moss. Apply lawn mosskillers in fine weather. Some require watering after 48 hours if there has been no rain. Check pack for details.

Mosskillers combined with a fertiliser are beneficial where grass vigour is low.

Feeding

In mid-spring use a proprietary spring or summer lawn fertiliser at the manufacturer’s recommended rates. Feeding the lawn will increase vigour and help prevent weeds and moss from establishing. Apply fertilisers when the soil is moist, or when rain is expected.

If grass loses its vigour and freshness between late spring and late summer, repeat the application of spring or summer lawn fertiliser or apply 15g per sq m sulphate of ammonia mixed with four times its weight dry soil. Mixing with soil ensures even distribution and avoids scorching the grass. Apply this mixture in cool, moist conditions and lightly water it in. As an organic alternative, use chicken manure pellets. Repeat fertiliser application a third time if needed six to eight weeks later.

Do not apply spring or summer lawn fertilisers, chicken manure pellets or sulphate of ammonia after August. They contain too much nitrogen for autumn use, encouraging green leafy growth at the wrong time of year, when it could be damaged by winter cold or pests and disease.

Over-seeding

After moss or weeds have been removed, or where grass is growing sparsely, over-seeding may be necessary. Early autumn is the best time for this job, but mid-spring is also suitable. 

• Break up the surface with a fork and rake it to make a reasonably fine surface.
• Sow grass seed at half the recommended rate or, where there are no recommendations, at 10-15g per sq m.
• Lightly rake to incorporate the seed into the surface.
• Where birds are a problem, net the area.
• If the weather remains dry for two or three days water gently with a sprinkler.
• Grass should sprout seven to 10 days after sowing.

In heavily used areas, choose a hardwearing utility mix containing ryegrass. Most lawn grasses do not thrive in shade, so for these areas choose a shade-tolerant mix.

Waterlogging

Lawns can become waterlogged if water sits on the surface and drains slowly. Waterlogging is more likely to be a problem on compacted and clay soils.

Pricking or slitting the surface can improve a waterlogged lawn. Shallow, 2-3 cm, pricking or slitting will help. However, deeper spiking is better, especially with a tool designed to leave holes 10-15 cm deep. These holes can be filled with a free-draining material, such as proprietary lawn top dressings or horticultural sand. This allows the water to flow from the surface to deeper, less compacted layers

Hand spiking tools are available for the purpose, but an ordinary garden fork can be used. Alternatively, for larger lawns, use powered tools. Try a hollow tiner, which has hollow spikes and removes plugs of soil that are then swept up and removed.

Pricking and slitting are best carried out once the excess water has drained away, especially where machinery is to be used. In small areas where standing water persists, sweep it off the lawn and into the beds before spiking with a hand spiking tool or garden fork

If your lawn is prone to waterlogging, spike it every few years in autumn. This will prevent the need for emergency action after wet winters.

Applying fertiliser in spring will help the grass to recover from winter damage and to grow more extensive root systems that are better able to withstand drought and flooding

Feeding in autumn with a lawn feed, rich in phosphorus, promotes good root growth

Wet soils and dead patches allow mosses to thrive in the lawn over winter. Remove these with a proprietary moss killer to allow the lawn to thrive.

Dogs

Dogs can cause unsightly patches on lawns, especially if they frequent the usual spot.  This is because their urine contains high levels of nitrogen which damages the lawn and causes small, characteristic brown patches. Lawns that are suffering from drought, disease, or are newly sodded or seeded are more susceptible to lawn burn.

Reduce the stress on your lawn by not over or under fertilising and by watering frequently. Encourage your dog to use less conspicuous areas to urinate in. If practical you can dilute the nitrogen in the soil by watering in the affected areas shortly after your dog has visited. 

Watering

Even if lawns turn brown and dry over summer, they usually recover well when rains return. Watering is usually not necessary over summer.

Looking after new lawns

Avoid using new lawns heavily in their first season.

Newly laid lawns can be fed like established lawns. They need watering, but should not be over watered, as this may result in shallow rooting and poor establishment.

Problems

When over-seeding the lawn, it can be difficult to match the colour of a new seed mix with your existing lawn.  In such circumstances it may be necessary to over-seed the whole lawn to achieve uniformity of colour and texture.

Areas of dry shade, such as under trees, become sparse very quickly despite adequate care. Consider over-seeding on an annual basis to maintain a dense sward. However, in very shady or high traffic areas grass just will not thrive and replacing grass with paving, gravel or bark mulch may give better results.

Spring is a good time to repair damage to lawns caused by pests, diseases or mechanical damage.