Don’t let creeping bellflower sneak away from you

The purple flowers are beautiful, and bees love ’em. But creeping bellflower is a European invader, and it’s a master at taking over gardens and lawns, crowding out native species.

This sneaky plant, also known as rampion, was likely brought to the U.S. during the early years of white settlement. Unfortunately, this reminder of home, like dandelions (another European introduction), can soon get out of control.

When Campanula rapunculoides first pops out of the ground in the spring, its leaves may look like the leaves of violets or self-heal (also known as heal-all or Prunella vulgaris), which is often recommended for use in bee lawns. It also looks like a native bellflower, Campanula americana. The major difference is that the native plant has flowers at the tips of its stems while the creeping kind has flowers going all the way up the stem. It plants itself in areas where the soil has recently been disturbed.

Despite its beauty and its attractiveness to bees, creeping bellflower is a menace to other plants in the neighborhood, crowding out desirable native plants that are needed by some bee species such as the Rusty-patched bumble bee, which is endangered in Minnesota.

What makes this plant so good at reproducing? It has two ways of perpetuating its species: Seeds and roots.

University of Minnesota Extension scientists estimate a single plant can produce as many as 15,000 seeds after the plant has flowered.

It also spreads through a stealthy underground system of roots and rhizomes, sending up another plant wherever it finds room to do so.

July and August are prime blooming months for creeping bellflower, as homeowners throughout the Northeaster’s coverage area can attest. They’re also good months for weeding this intruder out of your lawn or garden.

You can gain partial control by snapping off the flower heads before they go to seed. You’ll have more success, however, if you remove the plants in their entirety. It’s not an easy task.

You can try smothering the plants with a tarp or newspaper.

Mechanical removal is probably most effective. You’ll want to moisten the soil, then grab a spade or pitchfork to get under those roots and shoots. If you try to just pull the plant out, it can easily break off at the soil surface, leaving its rhizomes behind to regrow or start another plant in another location.

If you have a large patch of creeping bellflowers, you may want to take the chemical route. The U recommends repeated treatments of dicamba or triclopyr. Glyphosate can also be used; however, it’s a nonselective herbicide that kills nearly everything it touches. Herbicides should be applied in the fall. Whatever product you choose, be sure to follow the directions on the label.

There’s one more way to control creeping bellflower: Eat it. According to Alan Bergo, “The Forager Chef,” the plant is edible. He cooks the leaves as you would spinach or collards and uses the flowers in salads.

However you choose to remove creeping bellflower from your landscape, Ann Thureen, a Hennepin County Master Gardener who lives in the Audubon Park neighborhood, cautions against putting the plants in your home compost bin or in the city’s yard waste collection. “It’s best to bag the flowers (with seeds) and put them in the trash,” she said.