I’m not saying anything new to long-time gardeners, but creeping bellflower, botanically known as Campanula rapunculoides, is one evil plant. Frankly, it’s a garden cancer, spreading rampantly everywhere and entwining itself around the roots of any plant in its way.Yes, it has pretty bell-shaped flowers in a lovely shade of almost-periwinkle, growing up two-foot-or-so stems, and yes, some people like it. The positive comments usually come from new gardeners unfamiliar yet with its wantonly evil ways.
I’ve heard gardeners say it quickly took over a difficult place where nothing else would grow, filling the large void at their summer cottage in no time at all, or quickly beautifying the dry sandy patch beside their house. A neighbour once called me over because someone had told her she had “the rare Persian bluebell” growing in the middle of her hedge. You can imagine my horror when I saw what it was, and I had to ask why she thought a rare plant would somehow start to grow in a dense hedge. Thank goodness she lived two streets away, although the despicable bellflower had already invaded my garden. When I think of it, maybe it was my plant that invaded her garden…
Yes, it can spread that far. I don’t know where mine came from (besides hell), but it spread from the back garden to the front in two seasons, despite my efforts to get rid of it. What did I do? The same as I do with the almost as invasive lily-of-the-valley: I dug (and dig) it out spring and fall and sometimes in between. The blasted plant has large carrot-like roots that look like grasping white fingers, and I learned quickly that I had to dig down a good foot to get to them.
Trowel-digging and pulling up the hairy upper roots only encourages it to greater growth.
Deep digging, however, accomplished nothing and this past spring I realized the plant had spread to fill a roughly five-by-three-foot patch right in the centre of my front garden, wrapping around the roots of some thymes and ‘May Night’ salvia and making its way into ‘The Fairy’ roses. I got out the shovel again and dug up everyting, the bellflower, the salva and thymes (but not the roses–they’ll have to vanquish the bad guy themselves). Then I separated the good roots from the bad, replanted the good ones and stomped all over the bad ones. Believe me, they didn’t go into the compost bins.
In past years, especially in areas where the bellflower is growing closely with plants I really don’t want to dig up, I’ve tried Roundup, painting it on the leaves with a small artist’s brush to avoid nearby plants. I must say, the neighbours often wonder about me. Roundup contains glyphosate, the ingredient that kills broad-leaved plants, but unfortunately it’s now banned for cosmetic killing in Ontario, where I live. If you live here too, perhaps you have some left over from your attack on the poison ivy at the end of your garden, for which glyphosate is allowed. You’ll need lots, though–I’ve had to apply it two or three times to kill this nasty plant.
Creeping bellflower is sometime mistaken for Adenophora confusa,or ladybells, which are indeed more ladylike and don’t try to take over the garden. The blooms are almost identical, but Adenophoro has only fibrous roots, not the tuber-like roots of Campanula rapunculoides. (Both are members of the Campanulaceae family, by the way.) In the back garden I have other campanula, such as C. glomerata and C. persicifolia, growing in close proximity to the creeping bellflower, and sometimes it’s hard to tell the difference in the foliage. I’ve learned to look for creeping bellflower’s telltale reddish main stems, especially near the base of the plant, and the heart-shaped toothed leaves that get narrower the higher they grow on the stem.Leaves near the top are nearly stemless. The bell-shaped, five-lobed flowers have five stamens.
I try to dig plants out long before they get to the flowering stage because one strong plant can produce up to 15,000 seeds. Propagation from the roots is enough, thank you.
Somewhere I read that the leaves of Campanula rapunculoides have a pleasant mild flavour good in salads, and the young roots a sweet nut-like flavour.
Maybe making it a popular trendy new vegetable would be the best way to get rid of it.
Let’s compare notes: Do you have a pretty but invasive plant that’s taking over your garden? Tell us about it–maybe we can help.