Help us achieve our goals:
make a donation »
Join the RHS today and
support our charity
Free personalised gardening advice
RHS members get reduced ticket prices
RHS members get free access to RHS Gardens
Reduced prices on RHS Garden courses and workshops
020 3176 5800
Mon – Fri | 9am – 5pm
Make a donation
Join the RHS today and support our charity
I have forgotten my password
Keep me signed in
Register for free to receive our newsletters, add comments to blogs/articles and to save content.
Horsetail (Equisetum arvense), often called mare’s tail, is an invasive, deep-rooted perennial weed that will spread quickly to form a dense carpet of foliage, crowding out less vigorous plants in beds and borders.
Horsetail is an invasive, deep-rooted weed with fast-growing rhizomes (underground stems) that quickly send up dense stands of foliage.
Horsetail is easily recognised by its upright, fir tree-like shoots that appear in summer.
In spring, fertile light brown stems, 20-50cm (10-20in) tall, appear with a cone-like spore producing structure at the end of the stems.
In summer, sterile green shoots develop into fir tree-like plants, 60cm (2ft) tall.
The creeping rhizomes of this pernicious plant may go down as deep as 2m (7ft) below the surface, making them hard to remove by digging out, especially if they invade a border. They often enter gardens by spreading underground from neighbouring properties or land.
Removing horsetail by hand is difficult. Although rhizomes growing near the surface can be forked out, deeper roots will require a lot of excavation. Shallow, occasional weeding is not effective and can make the problem worse, as the plant can regrow from any small pieces left behind. However, removing shoots as soon as they appear above the ground can reduce infestation if carried out over a number of years.
If horsetail appears in lawns, it can be kept in check by mowing regularly.
Infestations of horsetail can be weakened with weedkiller.
Remember: horsetail is persistent, and several applications – possibly over a number of years – may be necessary to completely eradicate the problem.
Weedkillers for gardeners (Adobe Acrobat pdf document outlining weedkillers available to gardeners; see sections 4 and 5)
Chemicals: using a sprayerChemicals: using safely and effectivelyChemicals: using spot and broad-scale weedkillersWeeds: non-chemical control
Couch grassGarden thugs: potential nuisance plantsGround elderIvy on trees and a ground cover weedJapanese knotweedRHS video: weed controlWoodrush in lawns
the RHS today and get 12 months for the price of 9
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
Register for the site or sign in to share your experiences on this topic and seek advice from our community of gardeners.
John W on 09/07/2014
Can Mares Tail be added to compost heaps without it regrowing?
We're a UK charity established to share the best in gardening. We want to enrich everyone's life through plants, and make the UK a greener and more beautiful place.
Join the RHS today and get 12 months for the price of 9