Plant Doctor Archive

Patchy lawn - 1

MY lawn is currently looking very brown and patchy. I don't think it has grass grub and we've certainly had our fair share of rain. I would like to have a green lawn. Should I be fertilising it?

PATCHES in lawns can be caused by many different things. Disease, pests, annual weeds which die off in patches, dog or cat urine, poor drainage, lack of water, lack of nutrients, uneven mowing - the list goes on and on. Now is a good time to put some work into improving your lawn, so here are my tips.

• If there are a lot of broadleaf weeds apply a lawn weedkiller, such as Kleen Lawn, Turfix or Turf Weed Control. Follow the label directions carefully. Once the weeds have died off, vigorously rake the whole lawn, scratching down into the soil surface so old bits of grass, moss and other debris come to the surface. Mow the lawn with the catcher on to pick up the rubbish, or rake it up.
• Use a garden fork to spike poorly drained areas. Push the tines into the soil as far as you can. Make holes around 10cm apart and rock the fork to enlarge the holes and create cracks below the surface.
• Sow more grass seed onto bare patches after first breaking up the soil to encourage good germination. Cover the seed with a very fine layer of soil or potting mix and water if necessary.
• Once the grass has started to regrow, feed with a lawn fertiliser. Some types you apply as dry granules, others as a liquid. The main nutrients they supply are nitrogen and iron, which are essential for a deep green lawn. Follow the directions carefully, especially aiming for even coverage so your lawn ends up deep green all over.
• If your lawn is kikuyu, don't fret - you can still keep it looking good. Just mow very frequently, up to once a week during the growing seasons of spring and summer. Although, with ample rain this summer, it just hasn't stopped growing!
• A golden rule - mow your lawn often. Try not to cut it back by more than one third of its height each time. It's far better to mow every week than to let it get long and scalp it.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.