We use cookies to allow us and selected partners to improve your experience and our advertising. By continuing to browse you consent to our use of cookies. You can understand more and change your cookies preferences here.

Coronavirus Read our latest advice

Tough garden weeds and how to kill them

Which? Gardening experts show you how to identify common weeds and the best method to get rid of them organically

Tough garden weeds and how to kill them

Knowing which is a weed and which is a plant you’ll want to keep isn’t always easy, so we help you identify some of the worst weeds out there.

Weeding is a thankless task, especially with the sort of weeds that return year after year. Of course, you can treat the leaves of any weed with a weedkiller – anything that contains glyphosate will kill the roots and underground stems called rhizomes as well.

But not everyone is happy to use chemicals in their garden, so we look at alternative ways to deal with difficult garden weeds.

Which? Gardening magazine explains what to do in your garden every month – try it for only £5 a month – subscribe online or call 029 2267 0000.

Ground elder

This weed has bright green leaves and white flowers and likes shady areas of the garden where it will spread and take over, encroaching into your lawn and flower beds. It has rhizomes, which are underground stems that can sprout an entire new plant, so it’s incredibly tricky to get rid of.

You just need to keep digging the roots and rhizomes out each time the plant regrows, although it might be job of many seasons. Throw the rhizomes in your green-waste bin (the composting process should stop the plant regrowing) or leave to rot in a bucket of water, which makes a smelly but nutritious liquid feed for your garden.

More advice about ground elder

Bindweed

Bindweed entangles itself around any plant or shrub in your garden and can form dense mats that overwhelm your borders. Identify it by the smooth, twirling stem, large arrowhead-shaped green leaves and big trumpet-shaped blooms.

If you’re persistent you can weed this plant out, by digging out as much as possible of stems and long white roots. As soon as it starts to regrow, remove the growth again. It will weaken and finally disappear from your borders – but keep a watchful eye out for regrowth every spring.

More advice about bindweed

Dandelions

There should be room for a dandelion or two in your garden as they’re great flowers for pollinating insects. If you’re happy to live with a few, keep them under control by deadheading the flowers before they form fluffy seedheads. But too many can just get out of hand and if they start intruding into your lawn or in any crevices between paving, they can be a real pain. Identify these weeds by the rosette of smooth leaves, with a roughly oval shape and jagged edges, and the bright yellow flowers held on stalks above the leaves.

The best way to rid yourself of this weed is to the take out the long, pointed tap root. Get a trowel or knife and dig down as far as you can along the root and try to dig it out whole. Any piece of root left will regrow.

More advice about lawn weeds

Nettles

If you’ve got a section of garden you don’t use, then a patch of nettles will provide food for some of our native butterflies. But if they’re encroaching on an area you use a lot, or are in your flower borders, they can be an unpleasant stinging pest.

Identify them by their heart-shape or oval leaves with serrated edges. They’re hairy and it’s these hairs that cause the stinging sensation if your skin comes into contact with them. Dead nettles (that don’t sting and have white or pink flowers) have rounder, less hairy leaves.

Nettles have creeping roots and you can get rid of them by digging them out. They don’t like being cut down regularly, so this is also an option during the growing season. Throw the roots and leaves into a bucket of water to rot down, which forms a nettle-tea plant food your garden will love.

More advice about nettles

Horsetail

Horsetail is another weed that produces rhizomes and any fragment left of these can create another plant. Identify horsetail in early spring by its brown stem with a spore-containing cone on top. Once the cones have disappeared, the stem produces rings of long, needle-like leaves turning green.

If you don’t have the energy to dig it out year after year, you can try changing the conditions where it’s growing. It likes moist soil, so try improving the drainage in that area by adding sand or gravel. Horsetail doesn’t cope well with shade, either, so you could try planting something pretty, such as epimediums, over it to shade it out.

More advice about horsetail

Back to top
Back to top