How to . . . get rid of weeds
by Rhiannon James
Like desperadoes in a classic cowboy film, weeds are leaner and meaner than their domesticated counterparts. They can ride into a garden uninvited, on the wind, attached to animals or hidden in plant pots, and quickly take over, stealing water, food and light from more delicate garden plants or crops. They usually don’t improve the look of the place either.
The best way to get rid of these plants is to tackle them early in the spring. Weeds are fast-growing and have a strong instinct for survival – some produce thousands of seeds while others have systems of roots or stems that can quickly spread so it’s much easier to remove them while they’re still at the seedling stage.
Before repelling all invaders though, it’s worth checking quickly whether any of them could prove useful. Some weeds are good for wildlife while others are edible – for example, hairy bittercress and dandelion leaves can both be used in salads. It’s also possible that a weedy-looking specimen could be the offspring of self-seeders planted in the garden or a free gift from a nearby plot.
Things you’ll need
1. Some weeds can be pulled up by hand but you might also need a hoe, a hand fork and/or a garden fork.
2. Something to collect the weeds in (we use two old carrier bags: one for annual weeds, which can be composted as long as any seed heads have been removed, and another for perennial weeds which should be disposed of).
3. A pair of gloves
First, know your enemy
Understanding a bit more about the different types of weeds is a help when it comes to getting rid of them. There are three major groups:
1. Annuals: these weeds germinate from a seed, grow, flower, set seed and die in one season. Ephemeral weeds, such as chickweed and annual meadow grass, are even speedier – they can go through the whole process in a few weeks and the seeds they produce then repeat the same cycle, meaning this type of weed can rapidly take over a plot. It’ll save a lot of work if you can remove these weeds, by pulling them out or hoeing, before they have a chance to establish.
2. Biennials: this type takes two seasons to produce seeds and then dies away. Biennials need to be pulled up in their first season.
3. Perennials: these weeds, such as dandelions and couch grass, live for many seasons. They have a variety of ways to survive and multiply including seeds, spreading systems of stems or roots, and the ability to regenerate from fragments of stem or root left in the soil. To banish these weeds for good, all parts of the plant, both above and below the ground, need to be removed.
Removing weeds: step by step
1. Pulling weeds: the odd annual or biennial weed (or perennial seedling) is pretty straightforward to deal with – it can just be pulled out of the soil. Hold the plant close to the ground and haul it out. If you’ve got an area of weeds to clear though, it can be easier to use a hoe.
2. Using a hoe: using a hoe is a faster way to deal with annuals, biennials and perennial seedlings than weeding by hand. The idea is to slice off the weeds just below the soil surface and hoeing is best done on a dry, sunny day when the seedlings will shrivel on the soil surface and won’t re-root. There is a bewildering variety of hoes available but Dutch and push-pull hoes are amongst the best types for weeding. Choose one that has a handle long enough for you to stand upright as you use it. Slide the blade backwards and forwards, just below the soil surface, to sever the tops of the weeds from their roots. A Dutch hoe will slice through the weeds on the forward thrust while a push-pull hoe has a double-edged blade so it will cut on both the forward thrust and the backward pull. You’ll need to keep the blades sharp to slice through the weeds effectively. If you’re only dealing with a small space, you could also try using a hand hoe. Hoeing will also break up the surface of the soil, helping it to retain water.
3. Forking out: perennial weeds, such as couch grass and ground elder, which spread by means of rhizomes, tubers, runners or other vegetative means, have to be completely removed both above and below ground or they will re-grow from any remaining sections of root or stem. Starting a little distance away from the plant, use a fork to loosen the soil a bit and then slowly and smoothly lift the weed out. Then, try to remove any bits of stem or root that have broken off from the main plant. Check back a month later and remove any re-growth.
Perennial weeds with tap roots, such as dandelions, need to be dug out in the same way.
4. Repeated cutting: an alternative method for dealing with perennial weeds is to repeatedly cut down their top growth. This will force them to use up their food reserves and they will gradually weaken and die. Persistence is the key with this approach.
When doing any of the above, take care not to damage garden plants as you remove the weeds. If any weed is becoming a persistent or serious problem, then it’s best to seek out advice for that specific plant.
Other ways to control weeds
1. Mulch: adding a thick layer of mulch on top of the soil in early spring will deprive any weed seeds of the light they need to germinate and grow.
2. Pack in the plants: when garden plants grow close together, they shade the ground and use up the available moisture in the soil, making it difficult for weeds to grow.
3. Weed-suppressant fabrics: these are useful for covering areas of recently-cleared soil as they will prevent weeds from re-establishing. There are various different types available – none of them look that attractive but you can cover them with a layer of mulch. A membrane won’t solve the problem of existing perennial weeds in the soil though. Although they won’t grow through the fabric, they will creep along underneath it and come up through any planting holes you make.
4. Put new plants in quarantine: when you buy, or are given, plants, it can be useful to wait a few weeks before you put them in the garden. This allows you to remove any weeds that appear while the plant’s still in the pot and helps to avoid introducing them into the garden.
5. Weedkillers: unless you’re an organic gardener, you could use a weedkiller if all else fails. Contact herbicides work for annual weeds and perennial weed seedlings but for established perennials you’ll need a systemic herbicide which moves into the root system of the plant. The best technique is to pick a dry day and spot treat individual young weeds that are actively growing.
Differentiating between weeds and garden plants can be tricky when they’re all quite small but over time, the main offenders in your garden will probably become far too familiar. Some of the most common weeds are:
Hairy bittercress (Cardamine hirsuta)
This small weed matures very quickly, is able to flower at almost any time of the year and can produce thousands of seeds which are scattered all over the garden thanks to its explosive seed pods. These seeds are able to repeat the same cycle very quickly but can also survive in the soil for long periods of time, causing problems for many years to come. This weed has to be kept in check by hand weeding or hoeing before the flowers have a chance to set seed.
Fat hen (Chenopodium album)
It’s often said that one large fat hen plant can produce up to 70,000 seeds so it pays to get rid of this weed as quickly as possible.
Chickweed (Stellaria media)
Chickweed is very fast-growing and can germinate, flower and produce seed all year round. The seeds are also able to survive in the soil for decades and so this weed can cause problems over a very long period.
Shepherd’s purse (Capsella bursa-pastoris)
This common annual weed can flower at any time of year. When ripe, the heart-shaped seed vessels split in two and numerous seeds drop out.
Procumbent yellow sorrel (Oxalis corniculata)
Some Oxalis species are grown as ornamental garden plants but this particular specimen, which has green or purple clover-like leaves and bright yellow flowers, is a troublesome weed. It usually regenerates each year from seed like an annual and spreads rapidly in this way but its stems can also root if they touch the ground. Its seed capsules explode, scattering seeds over a wide area. Repeated hoeing will prevent the plant forming seeds and will gradually weaken it until it dies.
Dandelion (Taraxacum officinale)
Dandelions have a thick, fleshy tap root. This root can grow to a surprising depth but all of it should be dug out – any tiny piece left in the ground can grow into a new plant. Dandelion seeds are attached to the downy parachutes which are carried around the garden by the wind.
Stinging nettle (Urtica dioica)
This herbaceous perennial has a mass of spreading rhizomes, roots and also stolons which need to be dug out. They are usually yellow in colour and so are a little more easily recognised than those of other plants. It’s important to remove nettles before they have a chance to set seed.
Creeping buttercup (Ranunculus repens)
Creeping buttercup flowers from late spring to late summer and can produce many seeds. It also spreads by means of runners which root and form a new plant where they touch the soil. Dig out, making sure you remove all the runner tips.
Couch grass (Agropyron repens)
This is a perennial grass which spreads rapidly by means of rhizomes (underground stems). The rhizomes get in between the roots of other plants and are therefore very difficult to remove completely. Perseverance wins the day with this weed. Forking out or hand weeding are amongst the best ways to deal with this weed (as long as this will not damage any garden plants) but small pieces of rhizome left in the soil will re-grow – any new growth should be removed as quickly as possible.
Ground elder (Aegopodium podagraria)
This perennial weed is invasive. Spreading rapidly by means of white rhizomes, any small fragments left in the soil will quickly re-grow into a new plant. Ground elder can be carefully removed with a garden fork but you will need to check the soil regularly afterwards to get rid of any remaining pieces. If your garden plants have become entangled with the ground elder, you’ll need to lift them, carefully remove all traces of its rhizomes from their roots and then replant them in clean soil. If the weed is in an area of bare ground, you can cover it with black polythene until you kill it, this will take two to three seasons.
Hedge bindweed (Calystegia sepium)
Bindweed is an invasive weed that twines around other plants and smothers them. It spreads primarily by shallow rhizomes but it also has deep, rapidly-growing roots that are very brittle and difficult to remove. The plant can regenerate from any pieces of root left in the soil. This is a difficult plant to get rid of but persistent digging and hoeing over a couple of seasons can be effective.
Broad-leaved willowherb (Epilobium montanum)
This weed produces large numbers of tiny wind-dispersed seeds. Hoe or pull out seedlings and dig out more established plants, making sure no roots remain.
Bramble (Rubus fruticosus)
Brambles have long stems which can root easily when the tips touch the soil. It’s much easier to remove these plants while they’re still seedlings but if you’re tackling an established plant, cut it back and then dig out the stump – try to remove as much of the plant as possible as it will be able to regenerate from below the ground.