Weed Watch - Lesser Celandine
By Cathrine St.Clair
Because we’ve had some mild days, this weed is already starting to appear. So get ready to do battle if it is invading your personal space.
Lesser Celandine may have cheerful yellow flowers, but don't let it fool you. This is an aggressive, non-native thug that is wreaking havoc in our natural landscapes (not to mention front yards, back yards, flowerbeds and lawns).
Lesser Celandine (known as Ficaria verna but sometimes still listed as Ranunculus ficaria ) was brought from Europe in the 1860's as an ornamental plant and escaped cultivation. The plant has shiny, dark green, kidney shaped leaves and bright yellow flowers. It typically emerges in late January to early February.
Because it emerges so early and creates a very dense mat of leaves, it smothers many of our native spring wild flowers by blocking out light, air and growing space before they can even get started. Our native insects are then deprived of the pollen and nectar they need early in the season.
Lesser Celandine is an ephemeral and is usually dormant by late June. This can cause problems in wetlands because other plants have been snuffed out so there is not as much vegetation left to prevent soil erosion in late season flood events.
Lesser Celandine is a very vigorous spreader, mainly through underground tubers and bulblets attached to the leaf stems. It prefers moist soil, but can survive in drier areas. It can colonize an area very quickly.
The tubers and bulblets can be spread by animals, by flooding and even by well meaning gardeners. It is often seen along stream banks where it has been spread by water flow.
Managing Lesser Celandine is very difficult. Small infestations can be weeded out, but you must remove all the tubers and bulblets. Weeding can actually spread the weed if you are not careful. To help contain the spread, keep in mind:
Never put removed Lesser Celandine in the compost.
Do not pile it on the ground or rake it up, put it directly in a disposal container. You may need to dispose of some soil along with the tubers to ensure you have removed it all.
Mowing Lesser Celandine can fling the small bulblets into other sections of the lawn.
When the plant is dormant, its easy to move the tubers from one part of the garden to another when transplanting other plants.
It is possible to eliminate Lesser Celandine with herbicides, but the window of opportunity is small. Here are a few references that discuss the use of herbicides.
Pennsylvania Department of Natural Resources Lesser Celandine fact sheet
Brandywine Conservancy Invasive Species Spotlight: Lesser Celandine