As volunteer University of Minnesota Extension Master Gardeners, we hear different questions every year depending on the weather and which pests or plant diseases show up.
With the gardening season winding down toward fall, gardeners are still brimming with questions for the volunteers who staff information booths at the Fulton, Kingfield and Nokomis farmers markets.
Sometimes, the questions are unusual: Can I grow figs in Minnesota? How about a bird-of-paradise?
But we’re always certain people will ask about Japanese beetles, creeping Charlie and creeping bellflower.
Japanese beetles are close to being done for the season, but creeping Charlie and creeping bellflower are still going strong. Neither plant is native to the United States. Creeping Charlie will grow in deep shade where grass won’t. But it likes sun, too, and will romp through a lawn unless it’s restrained. Creeping bellflower has spires of beautiful bluebell-like flowers in summer but its lovely looks are deceiving. It will quickly take over a perennial garden.
Both of these aggressive plants can be removed without using chemicals, though it’s a challenge if they’ve gotten a head start. Pulling plants is always best but if you choose to use herbicides to eliminate creeping Charlie, now is a good time to do that. Autumn is the best time of year for systemic herbicide applications when creeping Charlie is actively taking up nutrients from the soil to sustain it through the winter.
Creeping bellflower has extensive root systems with large, tuber-like storage roots that will regrow from root pieces. Cutting off stems before they set seeds late summer is a good start to prevent new plants next year, and completely digging out plants is best. But if you need to try other herbicide methods, you should know that products containing 2,4-D are not effective on creeping bellflower. In non-lawn locations you’ll need to use a non-selective herbicide. Always explicitly follow product label directions for use and avoid wind drift onto other plants.
Don’t bother with mixing the supposed weed killer concoctions found online. Even familiar substances we use around the house can permanently damage soil, and they don’t work. For better information, go to the U of M Extension website, type the subject you’re curious about in the search box and you’ll get helpful and detailed information.
If you prefer to talk to someone, seek out Master Gardeners at the farmers market. We’ve been trained at the University of Minnesota and give advice based on university research. We can help with everything from growing apples to planting rain and boulevard gardens to caring for trees and shrubs. We also can help identify plants, bugs and diseases.
A sample stem and leaf of a mystery plant is helpful. Even better are photos. Close-up pictures of leaves and flowers as well as a photo of the entire plant are most likely to get a good identification.
More information about the county’s Master Gardener program is available at hennepinmastergardeners.org.