Earthworms

Britain has about eight to ten species of earthworms that are likely to be found in gardens. They vary in size and colour, but all have a role to play in creating good soil structure and fertility.

Soil casts from earthworms (Allolobophora sp. These can be a nuisance, particularly when they are smeared with a mower. Allow them to dry and brush them away before mowing.

Quick facts

Earthworms eat decaying plant material and do not damage growing plants
Britain has about 16 species of earthworms likely to be found in gardens
Earthworms occur in most soils
Earthworms can be used in wormeries to make compost
Worm casts can be a nuisance on lawns

What do earthworms do?

Earthworms are a familiar sight to gardeners and are useful in maintaing healthy garden soils;

  • Earthworms can be active throughout the year but are quiescent during cold or hot and dry weather. They occur in most soils, but are scarce in soils that are extremely acidic or prone to waterlogging
  • Earthworms eat decaying plant material and do not damage growing plants. They are important to soil structure and fertility
  • Some earthworms emerge at night to feed on dead plant material on the surface, and will pull fallen leaves and other plant debris into their tunnels
  • Some species such as Allolobophora nocturna, A. longa and Lumbricus terrestris live in permanent burrows and it is mainly these species that produce worm casts on the surface

Find out more about earthworms and participate in earthworm research at Earthworm Watch and the Earthworm Society of Britain (links to external websites)

Specialist species and wormeries

Some earthworm species live in accumulations of organic matter, such as compost heaps. One such species is Eisenia fetida (brandling or tiger worm), recognisable by its stripy appearance, another is Dendrobaena veneta. These are the species most commonly used in wormeries, as their feeding activities speed up the composting process.

Problems

Worm casts consist of soil and waste excreted by the worms as they feed on organic matter. Worm casts can be a nuisance on lawns and gravel paths.

Soil casts from earthworms (Allolobophora sp). These can be a nuisance, particularly when they are smeared with a mower. Allow them to dry and brush them away before mowing.
    Soil casts from earthworms (Allolobophora sp). These can be a nuisance, particularly when they are smeared with a mower. Allow them to dry and brush them away before mowing.

    Go wild for worms!

    This year the Wild About Gardens campaign, run jointly by the RHS and The Wildlife Trusts, is gearing gardeners up to go wild for worms. Learn how to encourage earthworms in your garden and download your free earthworm pack from the Wild About Gardens website.

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