Couch grass is a fast-growing

Perennials are plants that live for multiple years. They come in all shapes and sizes and fill our gardens with colourful flowers and ornamental foliage. Many are hardy and can survive outdoors all year round, while less hardy types need protection over winter. The term herbaceous perennial is used to describe long-lived plants without a permanent woody structure (they die back to ground level each autumn), distinguishing them from trees, shrubs and sub-shrubs.

A bud is a small, undeveloped shoot that contains the potential for new growth. Buds are typically found on stems, where they can be apical (found at the tip) or axillary (found between leaf axils) and may develop into leaves, shoots or flowers.

buds

Rhizomes are creeping swollen root-like structures that are actually adapted stems. Roots, stems with leaves and flowers are produced along its length. See plants such as Anemone nemorosa, bamboo, canna, border iris.

rhizomes

Couch grass has long been considered a weed by gardeners as, unlike other coarse grasses, it often grows among and through border plants as well as in lawns and on allotments. Those wishing to maintain immaculate, uniform lawns and tidy borders are likely to want to remove couch grass before it becomes established and spreads.  

However, couch grass is an important source of food for butterfly and moth caterpillars, including those of speckled wood and ringlet butterflies. Its swaying flower and seed heads also look attractive when grown in a meadow or species-rich lawn. As gardeners embrace “ecological gardening” and welcome a wider range of species into their gardens, couch grass is increasingly seen as a wildflower.

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Caterpillars of ringlet butterflies feed on couch grass 

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Couch grass flowers are an attractive addition to meadows

Here are our answers to your most common questions about dealing with couch grass: 

How

Invasive plants are those that grow vigorously, spread rapidly and can out-compete other plants. Native, non-native and cultivated plants can all be invasive.

invasive is couch grass? 

Couch grass didn’t earn its reputation as a weed for nothing – it spreads quickly once established. Plants come into growth and begin sending out new

Rhizomes are creeping swollen root-like structures that are actually adapted stems. Roots, stems with leaves and flowers are produced along its length. See plants such as Anemone nemorosa, bamboo, canna, border iris.

Established plants have been in their current location for two or three years and so have well-developed root systems able to support strong growth with healthy foliage and flowers.

Established plants

A seedling is a young plant grown from seed.

seedlings

Do I need to get rid of couch grass? 

Not necessarily – allowing couch grass to grow in a meadow, species-rich lawn, on a steep bank or in a wildlife patch or uncultivated area is a great way to support wildlife and boost the

The variety of living organisms (plants, animals, fungi and microorganisms) in a particular environment. Boosting the biodiversity of your garden has many benefits, including supporting wildlife, improving soil health and reducing the likelihood of pest and disease problems.

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A patch of couch grass and nettles will attract butterflies and moths 

What is the easiest way to kill couch grass? 

If you have couch grass growing where it is not wanted, there are a few ways to remove it: 

In borders 

• Avoid disturbing the soil – couch grass can regenerate from rhizome fragments, so avoid chopping them up by
  Hoes are multi-purpose tools for weeding (especially between rows of veg), loosening the soil surface, making seed drills, earthing up plants, and more. There are various types with different shaped blades. Hoeing to remove weeds is best done on a warm, dry day, so you slice easily through weed stems just below the surface.

  hoeing or digging over the soil where it grows.  
• Fork out individual plants – use a hand fork to tease couch grass and its roots and rhizomes from the soil. It’s often easiest to grasp a shoot and fork round it, gently lifting to reveal the roots that need to be dug out. This is best done in early spring before new couch grass plants become established and before established ones send out new rhizomes. Check for regrowth regularly throughout the growing season. 
• Lift border plants, clear the ground and replant – an option where couch grass is abundant in established borders and you don’t wish to leave the area bare (as below). Use a border fork to lift out and set aside border plants and then remove as much couch grass as possible. Take the time to work right through the area, teasing out as many rhizomes as you can find. Before replanting, examine the rootballs of your plants carefully to remove any hidden couch grass rhizomes. This is best done in early spring, when new couch growth is easy to spot and border plants are only just starting into growth. Fork out regrowth (as above) throughout the
  The period of time when an individual plant is in active growth. This will depend on the local climate and light levels, and can vary between different plants, although it is broadly from spring to autumn.

  growing season as soon as it appears. 
• Cover the soil to smother growth – a good option where couch grass is abundant in as yet uncultivated areas. Cut down couch grass stems, cover the ground with a layer of compostable material, such as cardboard, and cover that with a layer about 20cm (8in) thick of organic matter, such as
  Bark is the outermost layer of woody plants (trees, shrubs and woody climbers). It is several cells thick and provides protection against physical damage, disease and environmental stresses. Bark comes in a wide variety of colours and patterns, and these can help gardeners when identifying plants. The fissures and crevices of bark on older plants also creates valuable habitat for many garden creatures as well as lichens and small plants.

  bark or wood chips. Alternatively, use a heavy grade
  Anything that can be decomposed by fungi, bacteria and micro-organisms, so it doesn’t persist indefinitely in the environment. Biodegradable plastics are usually made from plants, such as bamboo, rather than fossil fuels. Ideally, products that claim to be biodegradable should break down quickly and leave nothing harmful behind. However, they may need specific conditions in order to biodegrade successfully or may produce greenhouse gases such as methane in the process.

  biodegradable
  Mulch is a layer of material, at least 5cm (2in) thick, applied to the soil surface in late autumn to late winter (Nov-Feb). It is used to provide frost protection, improve plant growth by adding nutrients or increasing organic matter content, reducing water loss from the soil, for decorative purposes and suppressing weeds. Examples include well-rotted garden compost and manure, chipped bark, gravel, grit and slate chippings.

  mulch matting. This will block out light and prevent growth, causing the root system to die. Leave in place for at least a few years, topping up the organic matter layer as necessary.

Teasing out couch grass with a hand fork is a good way to remove individual plants from beds and borders

 In lawns 

• Improve the health of your lawn – couch grass is less able to spread into and establish in dense, healthy lawns. Follow a programme of lawn maintenance in spring/summer and autumn to boost the vigour of your lawn. If patches of your lawn are struggling, overseed with a mix to suit the growing conditions.   
• Mow regularly – this will prevent couch grass from flowering and setting seed, helping to curtail its spread.  
• Fork out individual plants and repair bare patches – use a hand fork to lift couch grass plants and their rhizomes from the lawn. September is a good month to carry this out, as you can re-seed bare patches straight away. This is a good, easy option for quick results on small areas of lawn. Where couch is widespread within a lawn and cannot be tolerated, it may be necessary to strip off the turf, dig out the couch grass and re-lay or reseed the lawn.

  Top Tip

  Don’t add rhizomes, roots or seed from couch grass to your home compost bin, as it may not reach high enough temperatures to kill them. Instead, put them in your council green waste recycling bin or take them to your local recycling site.

Should I use weedkiller?  

No – although time consuming, couch grass can be controlled naturally, so there is no need to use a weedkiller. As couch grass is a grass species, there are no selective lawn weedkillers available that will kill it without also harming your lawn grass.  

For more information see our page on Weeds: non-chemical controls.