How to Identify Common UK Garden Weeds

Common Garden Weeds in the UK and How to Identify Them

So, let’s look at how you can identify the type of weeds you have in your garden and how you can deal with them.

Discover how to easily identify common garden weeds in the UK.
Learn which weeds invade lawns and how to stop them fast.
Uncover weed control tips without using chemicals.
Explore the difference between annual, perennial, and woody weeds.
Understand how invasive weeds like Japanese knotweed can damage your garden.

Annual Weeds

Annual weeds are those that last either a year or one growing season. They, however, produce a lot of weed seeds and keep popping up every year when the time is right.

List of annual weeds in the UK

Cleavers

Appearance - Cleavers have long but weak sprawling stems that can go up to one metre in height and have whorls with around six or eight slender green leaves, all with a notable central vein. This weed sprouts small white-green flowers in branching clusters between May and August. These flowers later develop into green or purple round fruits, which are around 4 mm in diameter.
Why is it problematic? - Just one plant of this variety produces between 300 and 400 seeds and worst of all, some of these seeds can persist in the soil and keep sprouting for up to six years. While these weeds are easy to remove when they’re still young, once they mature and start producing seeds, they become a huge nuisance.

Non-weedkiller solutions - Seedlings should be hoed or manually removed as soon as they’re spotted. To prevent the germination of cleaver seedlings, you can cover your lawn in opaque mulching film or bulky organic mulch, just make sure that the layer is at least 8 cm deep.
Herb Robert

Appearance - Herb Robert is an annual or biannual weed, which belongs to the geranium family. Its foliage is palmately divided, strongly scented and sometimes reddened, as are its stems. The pink flowers this weed produces bloom throughout spring, summer and even autumn. Herb Robert can grow up to 30 cm and is a weed that best thrives in shaded areas.
Why is it problematic? - Herb Robert is a weed that grows very quickly and has explosive seed pods, which if left unattended, flower and spread rapidly throughout the garden.
Non-weedkiller solutions - Pull Herb Robert weeds before they flower either by hand or by digging them up. Seedlings should be removed by using a hoe when the land is dry. To discourage the seeds of this weed from taking hold, cover your lawn with coarse bark mulch.
Bittercress

Appearance - Bittercress is a weed, which is a member of the mustard family of plants. It has tiny white flowers and pinnate leaves. It’s a very common annual plant in the UK and can be seen growing on the surface of containers, in gardening centres and even nurseries.
Why is it problematic? - Bittercress is a weed with an explosive seed mechanism and can disperse its seed up to one meter away from its base. This plant has a short life cycle but can appear at pretty much any time of the year. However, most commonly, Bittercress weeds pop up during summer or early spring. Being a hardy plant, it can withstand harsh winter temperatures.
Non-weedkiller control - Bittercress should be forked out or pulled out by hand before it has had time to spread its seeds. If you need to suppress this weed’s seeds, use either mulch, 15 cm deep or other organic matter like compost or tree bark.
Common Chickweed

Appearance - Chickweed is an annual weed that can grow on both cultivated and bare ground. It has bright green and pointy oval-shaped leaves, which grow in opposite pairs. These leaves clamp up towards each other during the evening to protect delicate new growth. Chickweed’s flowers are white in colour and shaped like little stars. This weed can flower during any time of the year but the flowers are most noticeable during spring and autumn.
Why is it problematic? - A single plant of Chickweed can produce up to 1300 seeds and it only takes five to six weeks for this weed to go from germination to seed dispersal. Chickweed seeds can be easily distributed through manure, compost, topsoil and even by birds and animals. These seeds can be so hardy that they can even survive passing through a bird’s digestive tract.
Non-weedkiller control - Remove Chickweed plants by hand or hoe before they begin flowering and setting their seeds. To prevent this weed’s seeds from germinating, you can place opaque plastic sheeting or mulch made out of wood chips over your beds. Just make sure the depth of the mulch is at least eight centimetres.

Lawn Weeds

Lawn weeds are very robust and if left unattended, they can suffocate the lawn’s grass. The most common weeds that fall under this category are plantain, daisies and dandelions.

Common lawn weeds in the UK

Dandelion

Appearance - Dandelions are fast spreading perennial weeds that form a large, flat rosette. This weed can germinate through any season. Due to their long stout tap roots, dandelions can be a pain to pull out. This weed’s leaves are long and fleshy and are usually between 5 and 25 cm long. Its single yellow flower grows throughout March till November.
Why is it problematic? - Dandelions are vigorous weeds that quickly kill the grass above which they grow. This weed is extremely difficult to remove, as its roots penetrate deep into the soil and if the whole thing isn’t pulled out at once, the roots generate a new plant. Dandelions tend to camouflage themselves as they adapt to mowing regimes. Meaning that if a lawn is well maintained, they won’t grow above grass level, while if it’s neglected, they will grow tall.
Non-weedkiller control - Dandelions can be pulled out by hand, however, if even a small part of the roots remain, the plant will regenerate. So, if you’re planning to weed out dandelions, do it while the soil is moist and use a small garden fork. Gently lift the weed and the area around it with the fork, while making sure to remove the whole plant including its roots.
Creeping buttercup

Appearance - Creeping buttercup is a perennial weed that thrives in moist soil. It grows on lawns, borders and bare soil. This weed has glossy yellow flowers that bloom between May and November. It may not bear flowers if the grass is mown regularly.
Why is it problematic? - Having this weed in your garden might mean that your soil needs structure and drainage improvement, as this weed grows best in moist soil, rich in clay. It spreads quickly with the help of long runners.
Non-weedkiller control - Before you do your first mow of the year in spring, use a wire-toothed rake to elevate developing runners. Then run them over with the mower. Also, be sure to aerate your lawn in autumn to improve its drainage.
Yarrow

Appearance - This broad-leaf perennial weed grows in most types of turfs, as well as meadows and hedgerows. Its leaves are fine and feathery and they are finely divided in linear segments. Yarrow’s flowering period is between June and September and the flowers it produces are small white or pale yellow in colour. If left undisturbed, this weed can grow up to 80 cm tall.
Why is it problematic? - This weed’s root system is fibrous and consists of multiple underground runners. Thanks to these runners, Yarrow is able to establish itself well on turf and can even withstand droughts.
Non-weedkiller control - Firstly, work on your lawn. Encourage healthy grass growth with the help of nutrients. Well-looked after and vigorous grass can prevent Yarrow from setting roots in your garden. Mow the lawn regularly, in order to prevent seed heads from forming. If Yarrow has already started to pop up, try hand-weeding it, just make sure to remove the roots, as well.
Daisy

Appearance - Daisies are amongst the most recognised weeds out there, with their oval to spoon-shaped leaves. Every daisy plant produces a circle of white flowers surrounding a yellow pistil in the middle. These flowers close during the night and open up during the day when there’s sunlight. They normally flower between March and October.
Why is it problematic? - Daisies are weeds with a fibrous root system, which allows them to spread either by seed or through underground runners. Since daisies grow very close to the ground, they can be a bit hard to mow.
Non-weedkiller control - The best way to prevent this weed from growing in your garden is by keeping your turf healthy and thick. Daisies prefer to grow in neglected areas where the grass has weakened and has lost its vigour. If you notice daisies growing in your garden, remove them as soon as you spot them. For this, use a small knife or a daisy grubber.

Perennial and woody weeds

What’s typical about perennial and woody weeds is that they produce big, creeping or deep roots, which help them pop up every year. These weeds can grow back even if only a small segment is left of them. So, keep in mind that digging them out can in some cases make matters even worse.

Common perennial and woody in the UK

Green Alkanet

Appearance - Green alkanet is a perennial weed that usually grows in damp and shady areas. It’s a member of the forget-me-not family of plants. Green alkanet has hairy stems and bristly leaves. It blooms between April and June and its flower is a bright blue with a white pistil in the centre.
Why is it problematic? - Green alkanet spreads quickly by self-seeding and can easily regenerate, thanks to its deep perennial taproot. New plants born from the main one will usually pop up around it in small colonies. In some rare cases, the seed capsules can be transported quite far away from the main plant by sticking on animal fur or clothing.
Non-weedkiller control - In order to get rid of green alkanet from your turf, you will need to dig deep to remove its roots. Seedlings can be weeded out either by hand or with the use of a hoe. Just remember to put some gloves if you will be pulling on the stems directly. Since this weed’s seeds can stay underground, dormant for quite some time, this weeding operation will be an on-going one. You can prevent green alkanet from germinating by spreading opaque mulching film over it at a minimum depth of 8 cm.
Couch

Appearance - Couch grass is an invasive perennial weed, which uses rhizomes to spread rapidly. Its appearance is that of normal grass but underneath the dirt, its roots form a dense network.
Why is it problematic? -This weed’s dense network of rhizomes can get entangled in other plants’ roots, causing big problems and making weed control very difficult. Since Couch is self-sterile, the weeds you see are most commonly from a single colony, as this weed doesn’t produce seed too often.
Non-weedkiller control - In uncultivated areas it’s possible to fork these weeds out of a lighter type of soil since its underground stem system is on the shallow side. However, this weed can leave behind small parts of the rhizome underground and quickly regrow to its former glory. If couch grass is popping up in a cultivated area, you can weed it out by hand. However, perform this in early spring, as during that time, it’s less likely to damage the roots of surrounding bushes and perennials.
Bindweed

Appearance - There are two types of bindweed - hedge bindweed and field bindweed. Both varieties are trumpet-flowered weeds that entwine into the stems of other plants and kill them in the process. In order to climb, hedge bindweed uses its strong twining stems. Visually, it has heart-shaped leaves and dons large white trumpet-shaped flowers. It most often latches on to hedges and shrubs and in some cases, even on ornamental trees. Field bindweed, on the other hand, is the weaker of the bunch with smaller pink or white flowers. Aside from its size, it closely resembles hedge bindweed.
Why is it problematic? - Bindweed weeds speed through their underground rhizomes. These rhizomes can penetrate deep into the soil, reaching up to five meters in depth. Bellbind weeds spread rapidly and quickly establish colonies, which can spread outwards by two metres or more in just a single season.
Non-weedkiller control - Bindweed is difficult to get rid of, as their roots penetrate deep into the soil. However, if you’re persistent with your forking and hoeing, you might get rid of these weeds in a couple of years. Forking should be performed during autumn and winter so you can remove as much of bindweed’s roots. When spring comes and new growth appears, dig it out. Hoeing, on the other hand, is ideal when digging is not an option. Aim to sever the weed at ground level using your hoe. This job, unfortunately, is not a one time deal and it will need to be repeated through the weed’s growing season.
Japanese knotweed

Appearance - Japanese knotweed is a quick-growing perennial weed, whose stems are tall and dense. It has invasive rhizomes, which can dig deep into any turf. During spring, purple-red shoots emerge at ground level. They then grow rapidly and by summer, produce dense bamboo-like canes, which can reach up to 2 metres in length. Japanese knotweed has heart- or shovel-shaped leaves, which can sometimes grow along the plant’s stems. This weed blooms between late summer and early autumn and its flowers resemble creamy-white tassels.
Why is it problematic? - Japanese knotweed is a deeply penetrating plant that is almost impossible to get rid of on your own. No matter what you try, chances are the weed will persevere. If this weed grows close to your home, it can send its rhizomes underneath your property and destroy the foundation.
Non-weedkiller control - If you have Japanese knotweed in your garden, chances are you will need to call a professional service to have it removed. Special knotweed contractors will have to be called to remove and dispose of this weed.

Now that you know how to discern some of the most common weeds in the UK, just keep on top of them by getting rid of them when they are still young or as soon as you spot them in your garden or on your lawn. Be careful with Japanese knotweed, however, as you will be committing an offence if you unintentionally facilitate its spread, while trying to remove this invasive plant. Call a professional instead!

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