What are worm castings?

At this time of year worms leave small mounds of earth, known as worm castings, on top of turf. So what are worm castings and where do they come from? Find out with helpful advice, and tips on how to remove them, from Essex turf grower Paynes Turf.

What are worm castings

What are worm castings?

Worm castings are the waste product from the guts of earthworms, which live in the soil all year round. The casts are made up of small mounds of earth which are usually wet and sticky, and can make a mess of the lawn if they are trodden on.

They are formed when earthworms excrete their waste product above the soil. Earthworms feed on organic matter that is already present in soil, for example dead plant material. As they ingest this plant matter they also ingest a little soil. Normally, earthworms excrete this waste product underground, however, when the soil is very wet (as is normal at this time of year) the worms tend to come up to the surface to breathe and feed, and then excrete.

Worm casts are not harmful to your lawn in any way, so never be tempted to try to remove them. In fact, earthworms are essential to the growth and overall health of your lawn – worms improve the structure of the soil and add vital nutrients which help the lawn to grown lush and green. They also help to aerate the soil, which in turn provides air to the roots of the grass, promotes strong growth, and helps to prevent drainage problems. The presence of worm casts on your lawn is a very good sign of worm activity and therefore, a healthy lawn. Worms are pretty awesome creatures aren’t they?

So what’s the best way to remove worm castings?

Firstly, you can help to reduce the amount of worm casts that appear on your lawn by making sure that you aerate it every year, especially if it is prone to becoming waterlogged. Find out how to aerate your lawn by clicking here.

Reduce the amount of dead plant matter by removing grass clippings after the lawn has been cut, and you will reduce the amount of worms that feed on it – just bear in mind that this could mean that fewer worms frequent your garden.

If you would like to remove worm casts from your lawn, simply leave them to dry out as much as possible before sweeping them away into the lawn using a garden broom with a stiff head.