Koenigia Species, Alpine Knotweed, Giant Fleeceflower, White Dragon

Have grown a clump of 2 of these plants for 3 years now. Absolutely well-behaved, non-spreading. They fill a corner of the fencerow, gett...Read Moreing about 6' tall and quite bushy. Covered with blooms which bees and butterflies love - beware, the flowers are a bit stinky - I wouldn't plant them close to a deck or other sitting area. The white flowers do turn browner toward summer's end, but to me this is not off-putting. They are a wonderful way to fill space quickly and require no special care.

This perennial is a well-behaved, long-lived clump-former, though anyone planting it should be prepared for its size---mature plants usua...Read Morelly get at least 6' high. Top growth may reach 8' across, but it doesn't require support in full sun.

It looks alarmingly like some closely related invasive plants (especially Japanese knotweed), but it doesn't invade natural areas and it doesn't spread beyond its usual clump size in the garden. Anyone with a plant sending up shoots 6 feet beyond the clump has a mislabeled plant.

It does have a very long summer season of bloom, and it looks good in its first flush of bloom, but I'm not as enthusiastic about this plant as many gardeners. Perhaps if I were willing to deadhead its spent flowers, I'd be more susceptible to its charms. But I dislike its appearance in late summer with all the disintegrating inflorescences mixed in among the new ones, and I'm not willing to do so much deadheading.

Usually sold in commerce as "Persicaria polymorpha", but this name seems to be erroneous. It appears to be a recently developed sterile hybrid of unknown parentage.

This grows very well in Zone3 in Calgary. I have had my clump for 8 years and it has just now begun to spread at a greater rate. Prior ...Read Moreto this year, the clump simply became wider and wider. Now, it is sending shoots 6 and 7 feet away from the mother plant. I am a bit surprised by this, but the shoots are easily uprooted. Love this plant, but can understand the concern in more temperate climates.

Not aggressive at all but does grow large so plant it in a location with space. A wonder full plant! Arthur in the Garden!

I just read all about this plant at http://www.overplanted.com
...Read More/> I bought my plant in 2006 and was amazed at its size, energy and attractiveness. It shares space with a Red Osier Dogwood, three varieties of grasses, Golden Ninebark and Diablo Ninebark, a low-growing Rhodendron and some yellow Daylilies.
This year, for the first time I have at least 5 offshoots, and I'm looking forward to transplanting them. I have to do some serious research on how to go about that.
P

This plant has grown very successfully in my zone 4 garden on the north side of my home in almost complete shade. It has grown larger bu...Read Moret not moved from it's own clump. Very beautiful. I am planning on dividing the clump this fall and spreading it out along the whole wall. Flowers last for almost a month!

This plant is an awesome performer in my garden. I have it in the back of the garden in part sun/ part shade with a large evergreen as a...Read More backdrop. It grows to about 5 feet in height and about 5 feet in width. I have day lilies at the base of this plant but I must move them this year because I am unable to see them very well because the girth of this plant.

It's very fun to watch this plant take shape because I swear it grows at least 5 inches a day!

My mother has this in her zone 6a garden three miles from me, and it is a beauty! It behaves itself, hasn't propogated itself beyond the...Read More clump it's growing in, and is a wonderful backdrop plant planted against her retaining wall.

Bold landscape plant with a shrub-like habit - excellent for a back border. Wonderful textured leaves with giant fluffy white astilbe-li...Read Moreke blooms in early summer. One of Wolfgang Oehme's favorite plants!

While this species of Persicaria is not the highly invasive Japanese Knotweed, it is related (see "Polygonum cuspidatum" in this database...Read More, previous scientific names of JP also include Polygonum sieboldii, Polygonum japonicum, Polygonum zuccharini Small, Pleuropterus zuccarinii, Polygonum reynoutria (in USA horticulture trade)).

Persicaria polymorpha is a clump-forming, apparently non-invasive cultivar that is highly ornamental, however, I've changed my opinion on Persicaria since I first obtained the plants a few years ago. I was surprised at how large and spread-out my Persicaria plants grew after the first year, to the point where it was a bit alarming. I suspect that they could regenerate very easliy from roots spreading, and since they are not a native American plant, and are related to a really invasive pest here in the Catskills (knotweed), I decided to eradicate the Persicaria from my gardens and not take any chances in being responsible for the spread of yet another invasive pest.

I have since replaced them with a beautiful white form of native butterly weed (Asclepias Tuberosa) that I got from a native plant nursery here in the Catskills. The white buterfly weed ( a white milkweed) has very nice looking foliage and blooms with large white flat flowers for a long period mid-summer, and looks great next to blue or purple native phlox as well. I highly reccommend the native butterfly weed.