(Allium ursinum) Wild garlic is a very attractive wildflower, which looks lovely in woodlands. However, in the garden it can be a difficult weed to control, if it grows where you don’t want it.
What is wild garlic?
Wild garlic is a very attractive wildflower, which looks lovely in its natural woodland habitat. However, in the garden it can become a problematic weed, mainly thanks to its spreading habit and persistent bulbs.
Although attractive when in flower, wild garlic can become a problem when allowed to become established, thanks to its numerous bulbs, especially when growing close to cultivated plants and in the lawn. If can soon spread and colonise and take over large areas of the garden.
Wild garlic is also known as ransoms.
Small and young leaves and flowers can be added to salads. Although cases of toxicity have been known when eating large quantities. Dogs seem to be particularly susceptible.
Where does it grow?
- Waste or uncultivated ground
Three-sided (triquetrous) flower stems accompany the 30cm (12in) long, deep green leaves from April to June. These produce flower heads (umbels) of white flowers at the top. Plants grow to 50cm (20in) high.
Both flowers and leaves smell of garlic.
Plants die down to their bulbs in summer, re-shooting in late November.
How to control wild garlic
As with most perennial weeds, never allow wild garlic to become established where you don’t want it to grow. This will make it more difficult to fully control it. Early eradication is important to stop it taking over the garden.
You can start by digging out the plants. However, this is fairly laborious and you have to make sure to remove the bulbs – some of which are very small. Sieving the soil with a fine-mesh sieve may be the only way of ensuring you have all the small bulbs.
Cultivating the soil from late autumn to winter may help weaken the plants.
Don’t put plants on the compost heap, as the bulbs can survive composting.
Covering bare soil with weed-control membrane (landscape fabric) or even thick black polythene will exclude light and may starve the bulbs, so they die. This can take a couple of years until the bulbs are completely exhausted.
Hoeing the plants will weaken them over time, but this will probably take several years to completely kill them.
In lawns, regular mowing throughout the year may weaken and eventually kill them.
There are a number of weed control options available to treat wild garlic. In addition to traditional weedkillers there are now also a range of more natural alternatives.
Contact weedkillers will burn and kill the foliage, but will have no effect on the bulbs. Constant spraying whenever leaves are present may weaken and kill them in time, although their foliage isn’t around for very long.
A systemic weedkiller, which is absorbed by the leaves, then moves down to the bulbs to kill them.
To ensure the weedkiller works effectively:
- Spray the leaves when the plants are growing actively.
- The larger the leaf area present, the greater the amount of weedkiller that can be absorbed. So don’t bother spraying when the growth first emerges through the soil – wait until the leaves grow larger.
- The most effective time is just before flowering.
- Use a fine spray to thoroughly coat the leaves in small droplets.
- Don’t spray when the sun is fully out. Ideally spray in the evening to prevent the spray evaporating and to give maximum time for the spray to be absorbed.
- One application of weedkiller probably won’t completely kill wild garlic. You may need to make repeated applications over several years.
Most contact weedkillers are total weedkillers – that is they will damage or kill any plants whose leaves they are sprayed on. Make sure you keep the spray off wanted plants – including lawns – and, if necessary protect plants by covering with polythene or similar when spraying.
Use weedkillers safely. Always read the label and product information before use.
Never allow plants to flower and set seed. Although this is pretty easy in your garden, it’s more difficult to stop the seeds blowing in from a neighbour’s garden, any surrounding fields and waste ground and even further afield.
- Hand fork
- Weeding tools
- Weed-control membrane