Q. We are in the process of restoring a Lehigh River bank with native plants. But the over 2000 beautiful spring natives we've put in are being choked by a thick blanket of lesser celandine that flourishes during the peak bloom of such natives as Dutchman's Breeches, Virginia Bluebells, Trillium and Trout Lilies. It was recommended that we use Roundup in February before the natives come up. I understand that the glyphosate in the Roundup is not severely evil. However the size of our area would require a major grant to purchase the amount we'd need. Pulling is tricky as the celandine produces little tubers along their roots that can stay behind. What are your thoughts on this? Literally hundreds of acres are affected.
- ---Ilse in Bethlehem
Luckily, Round-Up is not approved for use near water, and I doubt anyone would invite Federal prosecution by writing you that big grant check.
And hundreds of acres?! Removal of such a large number of plants along a river bank in any manner would lead to severe environmental devastation. And for what? To be able to risk replacing a plant that produces pretty yellow buttercup-like flowers and does a magnificent job of preventing erosion with different plants that thrived in a different era and may no longer have what it takes to compete in a world that's been dramatically changed by the presence of humans?
Nature doesn't favor natives—or so called 'invaders'. Nature simply provides a canvas, and the rules of Darwin decide the winners. It's not the same river as when those other plants first flourished; human activity has changed everything about it and the area around it. The best I can suggest is that you establish a nearby area that you can protect with deep edging in which to show off your natives. Any attempts to remove that much celandine will be expensive, time-consuming, immensely destructive to the environment, and run a high risk of failure.
BUT you might be able to get it out of some small areas to help establish that refuge without causing too much damage. There is a new class of alternative broadleaf herbicide that uses Iron as its active ingredient—and it's specifically labeled for use on this plant (although the label just calls it "creeping buttercup", they clearly mean lesser celandine). Just go slowly, and try and keep it away from that priceless waterway as much as possible, as all herbicides must contain some type of surfactant or they won't work.
Luckily, the surfactants and other inactive ingredients in natural products like this are designed to be gentle on the environment. And iron isn't a hormonal disruptor, like Roundup and many of the other chemical herbicides.
And smothering the plants with wood ashes is an ancient tactic I found suggested in the lesser celandine article at a wonderful "Modern Herbal" website, www.botanical.com. This might be another nice experiment for a small area. But please don't mess with any right near the river; lesser celandine is virtually invulnerable in wet areas, and the erosion you'd cause trying to get it out would be immense.
Q. We have a two-fold invasion of lesser celandine; in my planting beds and throughout our new lawn. There's so much in the lawn that we can't spot spray to get rid of it—it would kill the lawn, too. Thanks for any advice!
- ---Jen in Southeastern PA
And then care for the lawn correctly! Your location—in the mid-Atlantic/Northern part of the country—strongly suggests that, unless its zoysia, your lawn is composed of cool-season grasses. So for you, 'correct' means: never cut it below three inches, never cut it during a dry heat wave, and feed it only in the Spring and Fall.
And, as lesser celandine craves moisture, make sure you don't overwater the lawn. If we don't get rain, water deeply, but only once a week. If you see you're making headway, aerate the turf this fall to improve the drainage. (But if your lawn is always wet, you'll have to install drain tiles to fix the problem and start over to keep the celandine out. This weed beats grass any day in a sopping wet environment.)
Dig it out of the flower beds relentlessly. Be persistent, get the below-ground tubers, and be sure to get it out early in the season—before it drops little seed-like things that also grow new plants, just like the underground tubers. (To quote the Modern Herbal website: "In the early summer, when the leaves and stems are dying down, grains drop to the ground, each capable of producing a new plant." )
Then cover any bare ground in the flower beds well with shredded leaves or other non-wood mulch and install deep edging to keep the celandine out. And again, don't overwater!
And please dear listeners and readers, don't go around trying to wipe this plant out everywhere you see it because it's on some hit list. It's not going to go away—and that 'hit list' may well have been instigated by Monsanto or some other herbicide producer. Lesser celandine stabilizes wetland areas brilliantly, and the buttercup-like flowers are breathtaking in the Spring, inspiring literary tributes by the likes of C. S. Lewis, J. R. R. Tolkien, D. H. Lawrence, and—most famously, the poet Wordsworth who wrote:
"Pansies, Lilies, Kingcups, Daisies;
Let them live upon their praises;
…There's a flower that shall be mine,
'Tis the little Celandine."
Eyes of some men travel far
For the finding of a star;
Up and down the heavens they go,
Men that keep a mighty rout!
I'm as great as they, I trow,
Since the day I found thee out,
Little flower! - I'll make a stir
Like a great Astronomer.
From botanical dot com: "A Modern Herbal":
Throughout March and April, this cheerful little plant is in full bloom, but as the spring passes into summer, the flowers pale somewhat, and the whole plant looks rather sickly, the warmth of the lengthening days withdrawing from it the needed moisture. By the end of May, no flowers are to be seen, and all the plant above ground withers and dies, the virtue being stored up in the fibres of the root, which swell into the form of tubers. If the plant is dug up, late in the summer or autumn, these tubers are seen hanging in a bunch, a dozen or more together, looking like figs, hence the plant's specific Latin name ficaria, from ficus (a fig). By these tubers, the plant is increased, as they break off readily, each tuber, like a potato, producing a new plant. To eradicate this plant from any ground, it is necessary to remove the roots bodily, for if the plants are dug into the soil, they work their way up to the surface again, the stems branching as they grow upward from the tubers, and at every branch producing fresh tubers.