How to Kill Wild Garlic

Wild garlic – also called ramsons – is a familiar sight in British woodlands every spring. The broad green leaves and clusters of white star-shaped flowers carpet forest floors, filling the air with their distinctive garlicky scent. It’s one of the more recognisable common UK weeds.

But when wild garlic escapes into your garden, that same vigour becomes a problem. This native plant has been growing in Britain for over 1,500 years and is perfectly adapted to UK conditions. It spreads through two mechanisms simultaneously: seeds produced by those white flowers, and underground bulb multiplication.

What makes wild garlic particularly challenging is its ability to hitchhike. The bulbs hide in soil, compost, and the rootballs of new plants. Move any of these and you’re potentially spreading wild garlic to new areas without realising it.

Understanding the Plant

Wild garlic is a bulbous perennial that emerges in late winter, often as early as February – weeks before most garden plants wake up. This head start allows it to establish dense carpets of foliage before competition arrives.

The leaves are broad, bright green, and elliptical – up to 25cm long and 7cm wide. They grow directly from the bulb on twisted stalks and emit a strong garlic smell when crushed. This smell is your best identification tool and distinguishes wild garlic from poisonous lookalikes like lily of the valley.

From April to June, clusters of white star-shaped flowers appear on leafless stems. Unlike crow garlic, wild garlic flowers don’t produce aerial bulbils – only seeds. By midsummer the above-ground growth dies back completely and the plant retreats to its underground bulb, where it remains dormant until the following spring.

Underground, each bulb gradually produces offsets – daughter bulbs that form alongside the parent. Over time, a single bulb becomes a clump, and a clump becomes a colony. Vegetative reproduction through bulb division can account for up to half of wild garlic’s spread.

Why Wild Garlic Is Difficult to Control

Wild garlic presents several challenges. First, the dual spread mechanism means you’re fighting on two fronts – preventing seed production above ground while eliminating bulbs below. Second, the bulbs can persist in soil for years, waiting for the right conditions to sprout. Third, and perhaps most frustrating, wild garlic is easily spread unintentionally.

Every time you move soil from an infested area, you risk carrying hidden bulbs with you. New plants from the garden centre may have wild garlic bulbs lurking in their rootballs. Even homemade compost can harbour bulbs if wild garlic material was added.

This underground persistence puts wild garlic in the same difficult category as other spreading perennials like ground elder, bindweed, and lesser celandine – weeds that survive and spread through hidden root or bulb systems.

The dense carpet of foliage that wild garlic creates also makes it difficult for other plants to establish. It emerges so early and grows so thickly that it shades out competition – a particular problem in shaded borders where plant options are already limited.

Controlling Wild Garlic

Herbicide Treatment

For established infestations, a systemic weed killer offers the most reliable control. Glyphosate-based products are absorbed through the leaves and transported down into the bulb, killing the entire plant permanently.

Timing is important. Apply herbicide when wild garlic is actively growing – typically from early spring when the leaves are fully unfurled through to flowering. The foliage needs to be healthy and photosynthesising to absorb and transport the herbicide effectively.

Expect to need multiple treatments. A single application rarely eliminates all the bulbs, particularly in dense colonies where some plants may be shielded from spray. Plan for at least two or three applications over a growing season, and continue monitoring for regrowth in subsequent years. For particularly stubborn infestations, you may need the strongest weedkiller available.

Where wild garlic is growing among plants you want to keep, use a gel formulation that you can apply directly to individual leaves. This allows targeted treatment without risking spray drift to desirable plants.

Manual Removal

For small infestations or where herbicides aren’t suitable, hand removal can work – but requires thoroughness.

Dig out the bulbs when the soil is moist and the plants are actively growing, making them easier to locate. Use a hand fork to loosen the soil and lift out entire clumps, including all the small offset bulbs. Even tiny bulbs left behind can regenerate.

Check the area carefully after removal. Any bulb fragments or overlooked offsets will produce new plants. Repeat the process whenever new growth appears, gradually depleting the bulb population over several seasons.

Smothering

If you’re willing to sacrifice use of the area temporarily, smothering with light-excluding material can eventually kill wild garlic.

Cover the infested area completely with thick black polythene or weed membrane, ensuring no gaps where shoots can emerge. Leave in place for at least one to two full growing seasons. The bulbs will repeatedly try to send up growth, exhaust their energy reserves, and eventually die.

This method works best for clearing entire beds before replanting. It’s not practical where you need to keep existing plants in place.

Preventing Wild Garlic Problems

Prevention is far easier than control. Be vigilant about how wild garlic might arrive in your garden.

Inspect new plants carefully before planting, particularly if purchased from informal sources. Check the rootball for any suspicious bulbs or early wild garlic leaves. If in doubt, pot up the plant separately and monitor for unwanted growth before adding it to your borders.

Never move soil from areas where wild garlic grows. This includes soil stuck to tools, boots, and wheelbarrows. Clean equipment thoroughly after working in infested areas.

Avoid composting wild garlic bulbs in your home compost heap – domestic compost rarely reaches temperatures high enough to kill them. Dispose of dug-up bulbs through council green waste instead, or dry them out completely in the sun before disposal.

If wild garlic is present in neighbouring properties, consider whether it might spread under fences via soil movement or seed dispersal. A vertical root barrier can help prevent underground spread, though seeds may still arrive by wind. The same approach helps if you’re dealing with weeds growing through from neighbours.

A Note on Foraging

Wild garlic is entirely edible – the leaves, flowers, and bulbs can all be eaten. Many gardeners deliberately cultivate it for the kitchen. If you’re considering removing wild garlic, you might first want to harvest some leaves for pesto, soups, or salads.

However, be absolutely certain of your identification before eating any foraged plant. Wild garlic looks superficially similar to lily of the valley, which is highly poisonous. The reliable test is the smell – crush a leaf between your fingers. Wild garlic has an unmistakable garlic odour; lily of the valley does not.

Wild garlic is one of many common garden weeds that has both culinary value and invasive potential – the key is keeping it where you want it.

Common Questions About Wild Garlic

How does wild garlic spread so quickly?

Wild garlic spreads through two mechanisms: seed production (each plant can produce many seeds that remain viable in soil) and underground bulb multiplication (each bulb produces offsets that form new plants). It’s also easily spread by gardeners moving contaminated soil, compost, or plant rootballs.

Can I dig out wild garlic to get rid of it?

Digging can work for small infestations if you’re thorough about removing every bulb, including tiny offsets. However, any bulbs left behind will regenerate. For larger infestations, herbicide treatment is usually more effective and less likely to spread bulbs through soil disturbance.

Why does wild garlic keep coming back after treatment?

Wild garlic bulbs can persist in soil for years, and a single herbicide application rarely kills every bulb in a colony. You typically need multiple treatments over successive seasons, plus ongoing monitoring for any regrowth from bulbs that escaped treatment or seeds germinating from the soil.

Is wild garlic actually a problem, or can I leave it?

That depends on your garden and preferences. Wild garlic is a native plant that supports pollinators and provides excellent ground cover in shaded areas. However, it does form dense carpets that exclude other plants. In ornamental borders, it can become invasive. The choice depends on whether you value its vigorous growth or find it problematic.

How long does it take to completely eliminate wild garlic?

Complete elimination typically takes two to three years of consistent effort, whether using herbicides, manual removal, or smothering. The timeline depends on the size of the infestation and how thoroughly you tackle both the bulbs and any new seedlings that emerge from seeds in the soil.