Horsetail Taking Over The Garden

What's happening?

The RHS describes horsetail as a native perennial with deep rhizomes that needs regular management. Its rhizomes spread slowly but can be up to 2 metres deep, which makes them difficult to remove, especially when intertwined with the roots of other plants. They can easily cross boundaries, so horsetail may enter gardens by spreading underground from neighbouring properties, and small sections of rhizome can regenerate, so it is often spread unintentionally. Early spring shoots produce spores and the green shoots grow through the summer. Eradicating an established colony can take many years. The RHS says it is not necessary to get rid of it where it is among trees, shrubs or vigorous perennials, where it causes no significant competition.

What usually causes it?

• Rhizomes spreading underground from a neighbouring garden or from waste ground
• Small sections of rhizome moved on a fork, on tools or in soil, which regenerate
• Digging or rotavating, which breaks the rhizomes up and spreads them
• A long-established colony with deep rhizomes that has never been managed
• Spores from the early shoots, which the RHS says are short-lived and need damp conditions

Is it dangerous?

No. It is a nuisance and a persistent weed. The RHS does not support the use of weedkillers and recommends alternative methods, so there is no urgent action to take.

Can I fix it myself?

Follow the RHS methods: pull or cut the shoots as they appear, and keep doing it, which weakens the plant over time. Smother with a cardboard layer and thick mulch, or heavy matting. Do not dig or rotavate. Tolerate it where it grows among established plants and does no harm. Do not put horsetail in a home compost bin; use a council green waste collection or recycling site, as the RHS advises. If it comes from a neighbour, tell them, because it will keep returning.

When should you call a gardener?

Call a gardener for regular pulling, cutting and mulching of a bed that is overrun, or to clear and smother a larger area. It will not be cleared in one visit, so agree a programme over seasons rather than a one-off.

What will the gardener actually do?

• Identify the plant and map the area it covers
• Pull or cut growth at a regular interval through the season
• Smother with cardboard or matting under deep mulch where beds are cleared
• Advise on a programme over several seasons
• Remove the waste to a green waste collection rather than a home compost heap

Who fixes this

• Weeding and border care

Questions people ask

Sources & References

1. RHS: horsetail
2. RHS: non-chemical weed control