How to Kill Ragwort

Ragwort is one of the most dangerous common UK weeds – not because it spreads aggressively, but because of what it does to animals that eat it. The bright yellow flowers look cheerful enough, but every part of the plant contains pyrrolizidine alkaloids that cause permanent, cumulative liver damage.

The real danger is how the poisoning works. There are no early warning signs. An animal can eat ragwort repeatedly over weeks or months, each dose adding to the damage, until the liver finally fails. By the time symptoms appear – weight loss, jaundice, neurological problems – it’s too late. There is no cure.

This is why ragwort control matters so much near paddocks, pastures, and anywhere hay is produced.

Understanding the Threat

Ragwort is a biennial plant. In its first year, it grows as a low rosette of deeply-lobed, dark green leaves close to the ground. In the second year, it sends up flowering stems 30-90cm tall, producing clusters of bright yellow daisy-like flowers from June through to October.

After flowering and setting seed, most plants die – but if you cut them before they seed, they can become short-lived perennials, surviving 4-5 years and producing flowers repeatedly.

A single plant can produce up to 150,000 seeds. Those seeds remain viable in soil for 5-20 years, waiting for bare ground and the right conditions to germinate. This is why ragwort problems rarely go away on their own.

Why Dead Ragwort is More Dangerous Than Living

Living ragwort has a bitter taste that most animals avoid. Horses and cattle grazing on good pasture will typically leave it alone. The danger comes when ragwort dies or wilts.

Dead ragwort loses its bitterness but retains all its toxicity. Animals no longer recognise it as dangerous and will eat it readily. This is why ragwort in hay or silage is so hazardous – the drying process removes the warning taste while preserving the poison.

After spraying or pulling ragwort, never leave the dead plants where livestock can reach them. Remove and destroy them completely.

Legal Requirements

Ragwort is listed as an “injurious weed” under the Weeds Act 1959. While you won’t be automatically prosecuted for having ragwort on your land, you can be served an enforcement notice requiring you to control it if there’s a risk of it spreading to neighbouring grazing land or land used for hay or silage production.

The Ragwort Control Act 2003 established a Code of Practice for preventing its spread. Non-compliance with this code can be used as evidence in legal proceedings.

Natural England investigates complaints where ragwort poses a risk to horses or livestock on neighbouring land. If you have ragwort spreading onto your property from elsewhere, you can make a formal complaint.

How to Kill Ragwort Effectively

The best approach depends on the scale of your problem and whether you’re near grazing land.

Herbicide Treatment

Systemic weed killers are most effective, particularly on larger infestations. Glyphosate-based products kill ragwort completely, including the roots.

The ideal time to spray is during the rosette stage – either late autumn (September-October) or early spring before the plant bolts. At this stage, plants are actively growing but still small, and the herbicide can reach all the foliage easily.

Critical points for spraying near grazing land:

Remove all livestock before spraying. Keep them off the treated area for at least 3-4 weeks, and longer until all ragwort foliage has completely rotted down. Dead ragwort becomes more palatable and remains just as toxic.

Spray in good growing conditions – mild weather, no rain forecast, plants not stressed by drought. Stressed plants absorb herbicide poorly.

Selective herbicides like 2,4-D and MCPA are effective alternatives that won’t kill grass, though they may damage clover. For stubborn infestations, the strongest weedkiller available ensures complete kill.

Hand Pulling

For small infestations, hand pulling can work – but it requires care.

Always wear gloves. Ragwort toxins can be absorbed through skin, and prolonged contact poses a health risk. Pull after rainfall when soil is soft, gripping as close to the base as possible. You need to remove the entire root – fragments left behind will regenerate.

Pulling works best on seedlings and first-year rosettes. Once plants are established with deep roots, complete removal becomes difficult. You’ll likely need to repeat the process for two consecutive years to catch plants you missed.

Importantly, pulling disturbs the soil and can bring buried seeds to the surface, potentially causing more germination. It also creates the bare ground that ragwort seeds need to establish.

Dispose of pulled plants safely. Bag them for council collection, burn them (where permitted), or compost them in a contained system that reaches high temperatures. Never leave pulled ragwort where animals could eat it.

Preventing Ragwort Problems

Ragwort establishes most easily on bare or damaged ground. The best prevention is maintaining dense, healthy grass cover.

Avoid overgrazing – sparse pasture with bare patches is an invitation for ragwort seeds to germinate. Repair any poached or damaged areas promptly by reseeding.

Monitor regularly, especially in spring and autumn when seedlings appear. Catching ragwort at the seedling stage makes control far easier than dealing with established plants.

If ragwort is present on neighbouring land and spreading onto yours, document the problem and contact Natural England if direct communication with the landowner doesn’t resolve it.

Common Questions About Ragwort

Is ragwort illegal in the UK?

Not exactly. Having ragwort isn’t automatically illegal, but it’s listed as an injurious weed under the Weeds Act 1959. You can be served an enforcement notice requiring you to control it if it poses a risk of spreading to neighbouring grazing land or forage production areas.

Why is ragwort more dangerous when dead?

Living ragwort has a bitter taste that animals instinctively avoid. When the plant dies or wilts, it loses this bitterness but keeps all its toxicity. Animals no longer recognise it as harmful and will eat it readily – which is why ragwort in hay is so dangerous.

How many seeds does ragwort produce?

A single ragwort plant can produce up to 150,000 seeds, though typical figures are lower. These seeds can remain viable in soil for 5-20 years, which is why ragwort problems persist even after you think you’ve cleared an area.

Can ragwort poison humans?

Yes, though the risk is lower than for livestock. The toxins can be absorbed through skin with prolonged contact, so always wear gloves when handling ragwort. Eating significant quantities would cause liver damage, but casual contact isn’t dangerous.

When is the best time to spray ragwort?

The rosette stage – either late autumn (September-October) or early spring before flowering stems appear. Plants are actively growing, relatively small, and herbicide can reach all foliage. Avoid spraying stressed plants during drought or extreme temperatures.

Ragwort shares its status as an injurious weed with thistles, docks, nettles, and hogweed. The danger isn’t just to your garden – it’s to any livestock that might graze nearby. A systemic weedkiller applied at the rosette stage kills the entire plant before it can flower and spread thousands more seeds.