When is a weed not a weed?

Posted on Wednesday, August 28th, 2013

We can all name a few weeds, such as dandelions, bindweed and the dreaded Japanese knotweed. But what makes a plant a weed? Well, really a weed is simply a plant growing in the wrong place. So an errant gladiolus growing in a bed of roses could well be considered a weed, whereas gladioli in other situations could be a valued addition to the garden.

On the whole the plants that we consider weeds are categorised as such because of their highly competitive nature, which makes them difficult to control and can limit the growth of neighbouring plants. They may do this by forming mats of foliage which smother the plants below them, self-seeding so freely that they pop up anywhere and everywhere, or climbing around other plants and strangling them in the process. Basically weeds are the thugs of the garden!

But surely every bad boy weed has a good side? Well, yes, in most cases. Read on and see if you can find some comfort in the benefits which your garden weeds can bring. Please note that if you are considering using any of these plants for medicinal purposes you should consult your doctor first.

Stinging nettles

Urtica dioica and the smaller Urtica urens are probably best know for the stings they give us if we brush against them. However these irritating plants actually have a wide range of uses.

Culinary uses

You can cook the young leaf tips of stinging nettles in much the same way as you would spinach. They are great in soups and can also be used to make nettle beer. The foliage should not be eaten raw and only younger leaves (from plants less than 10cm high) used for cooking (older leaves have a gritty texture even after cooking). You can also dry the leaves to make a non-aromatic tea.

Chlorophyll extracts from stinging nettles are used as a green colouring agent (E140) in food and medicine.

Medicinal uses

An infusion of nettles can be drunk to treat conditions including anaemia, haemorrhoids, arthritis, rhuematism and skin complaints. Externally (eg as an ointment) it can be used for local relief of arthritis pain, gout sciatica, burns, insect bites, scalp and hair problems, neuralgia and nosebleeds.

Horticultural uses

Nettles only grow in fertile soil, so they are a good indicator of the nutrient levels.

Their hunger for nutrients makes them a great source of plant food. You can make a liquid fertiliser by steeping nettles in water for 2 to 4 weeks (weigh them down with rocks or bricks to keep them submerged). Burgon and Ball do an ‘organic plant food maker’ with an infuser to contain your nettles and allow their goodness to spread into the water – though an old bucket will work just as well! Dilute the resulting liquid 1 part to 10 parts water and use it as you would any liquid feed. Chopped up nettles are also a useful addition to compost and can help to speed up the composting process, just make sure you don’t add any roots to your compost or you’ll find nettles growing out of it!

Stinging nettles are a main food source for butterflies, so growing a few in your garden can help sustain the native populations and also give them somewhere more attractive than your veg patch to lay their eggs! Ladybirds also favour nettles and are very useful in the garden as they prey on garden pests such as whitefly.


Dandelions or, to be more accurate, Taraxacum officinale, are a well known weed in lawns and borders. The common name is derived from the French ‘dent de lion’, which translates as ‘lion’s tooth’, a reference to the jagged leaf edges. Folklore has it that you can tell the time by counting how many puffs it takes to blow the seeds off a dandelion seedhead…though gardeners are less inclined to do this as it spreads the seeds all over their garden! Here’s a more positive look at how you can use dandelions.

Culinary uses

You can blanche fresh dandelion leaves to eat them in salads or cook them like spinach (they are often mixed with sorrel). The flower petals can be made into wine.

The leaves and roots are used to flavour herbal beers and soft drinks, such as dandelion and burdock. The roots can also be roasted, ground and used as a substitute for coffee.

Medicinal uses

Dandelion is used in both European and Chinese medicine for a wide range of ailments because of its diuretic, laxative and anti-rheumatic effects, and its ability to stimulate liver function, improve digestion and reduce swelling and inflammation. Conditions it is said to improve include urinary disorders, gall stones, jaundice, gout, eczema and acne.


Common chickweed, Stellaria media, is a real pain in the garden as each plant produces 2,500 seeds in a season and the seeds can survive for up to 4 years, germinating at any time. It particularly likes heavy and fertile soils. But it does have a good side!

Culinary uses

Chickweed sprigs can be added to salad and cooked as vegetables. They can also be fed to domestic fowl and pet birds (the common name derives from the fact that chickens enjoy eating the plant).

Medicinal uses

Medicinally it can be used to ease rheumatism when taken internally. When applied externally (usually within an ointment) it is said to ease itching skin conditions, eczema, psoriasis, vaginitis, ulcers, boils and abcesses.

Field horsetail

Equisetum arvense, field horsetail, is a difficult weed to control and can spread rapidly, particularly on compacted soil. But it does have some uses.

Medicinal uses

The stems of field horsetail are an astringent that acts on the genitor-urinary system when taken internally and can be used to treat prostatitis, incontinence, cystitis and urethritis. It can be used internally and externally for haemorrhage. However it is an irritant and therefore best restricted to short term use.

Other uses

Another common name for field horsetail is ‘bottlebrush’. This derives from the fact that,from the Middle Ages up until the 18th century, it was used for scouring pots and pans. Due to its high levels of silica it has good abrasive properties.

Shepherd’s purse

With its purse shaped seed capsules, which ripen to eject seeds all over your garden, Capsella bursa-pastoris is a real pest. It’s an ephemeral plant, meaning that it can have several life cycles in a year, so the production of seeds just goes on and on! But there is some good news about this plant.

Culinary uses

The leaves of shepher’s purse (which is also know as witches’ pouches or pick-pocket) are rich in vitamins A, B and C and can be used in salads.

Medicinal uses

It can be used internally (usually in a tea or tincture) to stop bleeding (especially excessive menstruation, blood in urine, haemorrhoids, nosebleed and wounds) and for cystitis. Externally it can be used for varicose veins. In Chinese medicine it is also used to cool the blood.


Daisies (Bellis perennis) in a lawn can be a real problem as they form a mat of foliage which crowds out the surrouding grass. But they do have some real benefits.

Culinary uses

Young leaves, flower buds and petals of daisies have a pleasantly sour taste and can be added to salads.

Medicinal uses

Daisy flowers and leaves be taken internally for coughs and catarrh and externally for ruptures, varicose veins, minor wounds, and sore/watery eyes. They are used in homeopathy as a treatment for deep bruising.

The daisy has also been investigated for possible use in HIV treatment.

Other uses

While a nuisance in the garden daisies are very pretty and surely the world would be a drearier place if we couldn’t make daisy chains?!

Ground elder

Aegopodium podagraria is a real problem in beds and borders, where its rhizomes entwine with other plants. But it does have its uses.

Culinary uses

Young leaves of ground elder can be used in salads and soups, and as a vegetable.

Medicinal uses

It is believed that ground elder was introduced into the British Isles in medieval times when it was cultivated in monasteries for medicinal use. It is dedicated to St Gerard , who was invoked to cure gout (‘herb Gerard’ is another name for ground elder).

Ground elder is used as a mild sedative with diuretic and anti-inflammatory effects. It can be taken internally (dried and used in infusions) to treat gout and sciatica. Externally it can be used to treat haemorrhoids, gout, stings and burns. It is also used in homeopathy to treat arthritis and rheumatism.