Hardiness: USDA Zone 3a: to -39.9 °C (-40 °F) USDA Zone 3b: to -37.2 °C (-35 °F) USDA Zone 4a: to -34.4 °C (-30 °F) USDA Zone 4b: to -31.6 °C (-25 °F) USDA Zone 5a: to -28.8 °C (-20 °F) USDA Zone 5b: to -26.1 °C (-15 °F) USDA Zone 6a: to -23.3 °C (-10 °F) USDA Zone 6b: to -20.5 °C (-5 °F) USDA Zone 7a: to -17.7 °C (0 °F) USDA Zone 7b: to -14.9 °C (5 °F) USDA Zone 8a: to -12.2 °C (10 °F) USDA Zone 8b: to -9.4 °C (15 °F)
On Jun 28, 2012, anolha from Lake Hallie, WI wrote:
I hate this plant! It is so invasive I have yet to find a way to get rid of it. I have pulled it, dug it and removed roots 2 feet down when small and big and still it grows back. I have tried weed killers and that hasn't worked. It is spreading throughout my yard. I would never give this plant to anyone.
On Aug 6, 2011, flybynyte from Webster, SD (Zone 4a) wrote:
i have this plant growing all over the place---and, have no idea where it came from. growing in peonies, bee balm, coneflowers, and on and on. i have been pulling this invasive plant for years now. it just keeps returning.
On Jul 1, 2009, woodflower from Portland, OR wrote:
This plant is somewhat invasive. It will overtake less vigorous neighbors and the roots are easily transplanted. All the same, a beautiful plant that performs well. It is probably best kept as a container plant.
On May 18, 2009, anelson77 from Seattle, WA wrote:
After 2 years in a partly shaded, dryish spot, this plant has grown into a very dense clump 3 feet across. It blooms heavily for a long period. It spreads fairly fast by underground shoots but not in an invasive manner, as the new stalks come up next to the established ones. The long flower stalks lean over a wall and look great. I would not plant this in a perennial garden, unless its companions are also large, vigorous plants. I am using it as ground cover around shrubs, and it fills this bill well, being totally impenetrable by weeds.
On Nov 17, 2007, kd2000 from toronto Canada wrote:
I have found this plant to be a good performer and not overly invasive in my zone 4/5 garden. Easy care, adds nice early summer colour, and does seem to fair well in drought conditions. I do deadhead to prevent self sowing as they set a tremendous amount of seed if left to their own
On Oct 28, 2007, Gardenerplus from Middlebury, VT wrote:
If I never saw this plant again I would be happy. Here in the Champain Valley of Vermont it is worse than mint with a tap root that can be a foot long. As a professional gardener I spend more time trying to eradicate this plant than any other by organic means. I love plants, gardening is my passion and my job, but I do not like Adenophora Liliifolia.
On Apr 2, 2005, SalmonMe from Springboro, OH (Zone 6a) wrote:
Plants can be very freely self-sowing, bordering on weedy. Seeding can be minimized by diligent deadheading. Deadhead to a lateral bud after flowers fade. A secondary flush of flowers will follow proper deadheading. After second flush fades, cut down to basal foliage. Too much shade may cause plants to flop over.
On Nov 12, 2004, lmelling from Ithaca, NY (Zone 5b) wrote:
The member who said these were invasive was right - they can be, unless moved when young. I generally dig up the young plants in early spring when I'm doing my first weeding of the season. Pot them up and take the babies to our annual plant sale or plant them elsewhere. Still, I occasionally still get them popping up where they're not wanted. But the flowers are beautiful and long lasting - so they're worth the bother.
They like partial to full sun and moist but well drained soil. I've seen mine wilt during droughts, so keep watered if you are getting less than average rainfall. Wet conditions (as we had this year) don't seem to bother them.
On Jul 6, 2003, Karenn from Mount Prospect, IL (Zone 5a) wrote:
I have had this plant (in one place only) for 8 years. I planted it at the north side base of a 40 year old silver maple. At the time I was a very inexperienced gardener. It has never moved around, never flopped, and never grown "out of bounds". I can only assume that the prolific roots of the silver maple keep it in check. It is really attractive where I have it, where very little else can grow!
On Jul 4, 2003, JanFRN from St. Albert Canada wrote:
These are almost impossible to get rid of. They have taproots, and Roundup acts like Miracle Gro! I saw them at a plant nursery recently and couldn't believe people PAY for them!
This plant has been said to grow in the following regions:
Hyampom, California Kiowa, Colorado Mount Prospect, Illinois Charlevoix, Michigan Marshall, Michigan Redford, Michigan Royal Oak, Michigan Central City, Nebraska Cayuga Heights, New York Crown Point, New York Syracuse, New York Perrysburg, Ohio Springboro, Ohio Portland, Oregon Webster, South Dakota Middlebury, Vermont Lexington, Virginia Richmond, Virginia Kalama, Washington Seattle, Washington Birchwood, Wisconsin Lake Hallie, Wisconsin Marinette, Wisconsin Spooner, Wisconsin