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Lawn feeds and weeds

How to deal with lawn problems

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How to deal with lawn problems

Expert advice on dealing with the five most common lawn problems, including weeds, ants nests and dog-urine patches.


To keep you lawn in tip-top condition choose a great lawn mower with our Best Buy lawn mower reviews.

There are several common lawn problems that even the most experienced of gardeners can come up against. Here's what you can do about them.

Moss in the lawn

Algae, lichen and moss are symptoms of poor growing conditions, such as lawns that are underfed, poorly drained or in shade. Feeding, spiking and scarifying will help to eradicate them.

  • Algae is a green or black slime covering waterlogged areas of turf. Regular treatment with lawn sand will kill it, but it will return if growing conditions aren’t improved using the methods described above.
  • Lichen are plate-like structures that curl up at the edges when dry. Lawn sand can get rid of these, too, but they will return if conditions remain poor.
  • Moss is generally found in damp, shady areas, so is most common in spring and autumn. Moss killers can be used at these times. After a few weeks, rake out the dead moss and reseed bare patches. Good maintenance will prevent its return.

Lawn weeds

When a lawn is in poor condition and contains as many weeds as grass, a one-off weed and feed treatment can help.

In our trial, the best feeds and weeds reduced the weeds completely and gave the grass a boost, leaving a much better lawn at the end of the season.

We've reviewed own-brand products from Tesco, Wilko, B&Q and Homebase, plus brands such as Miracle-Gro, Evergreen, Westland, Bayer and Vitax. Head to our lawn-care product reviews to find out which products are our Best Buys.

Lawn diseases

  • Dollar spot attacks fine-leafed grasses, causing round brown patches about 10cm wide.
  • Fusarium patch (snow mould) first appears as small yellow patches, which turn brown and spread. Fluffy pale-pink fungal growth may appear in damp weather. It appears in autumn and early spring. Avoid walking on the grass in wet, cold and snowy weather.
  • Red thread disease attacks mainly fine-leafed grasses in late summer and autumn. Patches of bleached, reddish turf appear and, on close inspection, a small, red, needle-like fungus is attached to the grass. It weakens the grass and spoils its appearance, but does no further damage.

These diseases all thrive on poorly fed, waterlogged soil, so to avoid them ensure your lawn is well fed and aerated.

Lawn pests

  • Ants and mining bees cause small mounds on the surface of the lawn. These are annoying, but cause no lasting damage. Scatter them with a twig broom before you mow.
  • Chafer grubs eat grass roots, causing small yellow-brown patches on the lawn. Use the biological control nematodes. They are available by mail order and in selected garden centres.
  • Earthworms, although useful in borders, are a pest in the lawn. If worm casts are trodden in or mown over while wet, they smear, leaving bare patches of soil that can be colonised by weeds. Wait until worm casts are dry and crumbly, then disperse them with a twig broom.
  • Leatherjackets are large, grey-brown legless grubs that sever roots, which leads to irregular brown patches on lawns. A common sign that you have a leatherjacket infestation is damage to your lawn caused by birds, badgers and foxes digging them up to eat. If feasible, water the lawn and cover with polythene overnight to encourage the grubs to the surface. In the morning, remove the plastic and sweep them off. Alternatively, use the biological control nematodes.
  • Molehills are the very worst lawn eyesore. You could try putting down mothballs, creosote or disinfectant to deter the moles, but they tend to return if not killed. If they persist, you may need to call in a professional.

Yellow patches

  • Female dog pee causes patches of grass to turn brown. Watering the area can reduce the effect, but it may need reseeding.
  • Compaction of the soil and consequent waterlogging can cause yellow or brown patches. Aerate the soil in autumn.
  • Spilt oil will result in brown patches, so move the mower onto a hard surface before carrying out maintenance.

Fairy rings and toadstools

  • A fairy ring is a ring of toadstools that forms on the lawn and gradually gets bigger. Two rings of lush, green grass appear either side of it and the area between them turns brown or bare. To eradicate the ring, dig out the top 30cm of grass and soil, 30cm beyond the outer edge of the ring. Dispose of the soil carefully to ensure you don't contaminate any other areas. Refill with new topsoil and reseed or turf.
  • Toadstools often appear in lawns without causing problems. Sometimes they grow in a line following a tree root. Remove the root if the toadstools are becoming a nuisance. Otherwise, brush or rake them away as you notice them. With luck, this will be before the spores are released.