Lesser celandine (Ranunculus ficaria) is a cheerful sight in spring with its shiny, buttercup yellow flowers. However, its persistent root tubers make it an unwelcome weed in most gardens and control is usually necessary.
What is celandine?
Lesser celandine is a perennial member of the buttercup family. A British native, it is widespread in woods, hedgerows and on the banks of streams, but can also be found in gardens.
Appearance
This plant usually appears above ground in late February and usually dies back in late April. Lesser celandine is a low-growing plant, rarely reaching more than 5cm (2in) in height.
It has glossy, heart-shaped leaves and bears shiny, bright-yellow flowers in March or April.
The problem
What makes lesser celandine a weed in gardens?
- Lesser celandine grows from root tubers and spreads mainly by tubercles (bulbils) that form in the leaf axils and rapidly colonise disturbed soil. Occasionally, lesser celandine produces viable seed too
- Because of the short growing period, the plant may not be a problem in gardens – it can even provide colour at a time when the ground tends to look bare – but it can be a real menace in some situations
- Control is difficult due to the short growing season and the persistence of the root tubers
Control
Non-chemical controls
There are a number of cultural control methods to try;
- Attempting to dig out the plants often assists their spread as, unless great care is taken, this operation will distribute the tubercles (small tubers)
- Celandine can be troublesome among spring-flowering bulbs or plants such as primroses. Where bulb borders are heavily infested, it is best to lift the bulbs when dormant and plant them elsewhere for a season while the border is thoroughly cleared
- Mulching the surface of the soil with a 10cm (4in) deep layer of organic material may smother the weed, but this method is not always feasible
Chemical controls
Lawn weedkillers
- Celandine in lawns is difficult to eradicate, as it is resistant to most lawn herbicides. An application of a selective lawn weedkiller based on MCPA (e.g. Doff Lawn Spot Weeder, Westland Resolva Lawn Weedkiller, Bayer Lawn Weedkiller 2, Vitax LawnClear 2 or Scotts Verdone Extra) may considerably check growth, but will almost certainly need a repeat treatment in the following spring. The first application should be given early in the season (as soon as the leaves are fully developed), followed by a second application three or four weeks later
Glyphosate
- Remove all cultivated plants first and then use a glyphosate spray (e.g. Scotts Roundup, Scotts Tumbleweed, Bayer Glyphosate Kills Weeds & Roots or Doff Knockdown Weedkiller). If plants can't be moved, a ready-to-use spray (e.g Scotts Fast Action Roundup Ready-to-Use, Bayer Glyphosate Ready-to-Use Kills Weeds & Roots, Doff Knockdown Weedkiller Ready-to-Use) or gel formulation (Scotts Roundup Gel) can be used with care around garden plants. When treating, branches or shoots of garden plants can be held back, using canes, or by covering or screening while spraying, but make sure the weed foliage has dried before releasing branches or removing the covering
Residual control
- Bayer Long Lasting Ground Clear containing glyphosate/flufenacet/metosulam comes in a soluble sachet. It can be applied once a season to natural surfaces where no plants are to be grown, and can also be applied under and around established woody trees and shrubs, including roses. This product kills off existing small green growth and prevents or checks developing growth. Check manufacturer’s recommendations before use to avoid damaging sensitive plants
Downloads
Weedkillers for gardeners (Adobe Acrobat pdf document outlining different weedkillers available for gardeners; see sections 1b, 4 and 5)
Links
Chemicals: using a sprayer
Chemicals: using safely and effectively
Chemicals: using spot and broad-scale weedkillers
Quick facts
Common name Lesser celandine
Botanical name Ranunculus ficaria
Areas affected Beds, borders, areas planted with bulbs and lawns
Main causes Weed with persistent root tubers
Timing Seen spring; treat in spring