I'm marking my experience as "negative" because in the long run it is a non-native and has eventually run amuck. I transplanted one plant...Read More from a nearby marina about 15 years ago. It spread VERY slowly...maybe only from one plant to a 10 sq.ft. area. However, in the past two years the growth has accelerated....and doubled. I tried to dig some up to reduce its presence and "oh boy!" I now see why they say it's nearly impossible to eradicate. I thought I was thorough, but 3 weeks later, there are lots of new spouts. It is absolutely beautiful when in bloom. So, the bottom line is: if you can contain it and monitor it, it might be worth having a bit of it. If I knew then what I know now, I would not plant it.
It does not spread by seed in this part of the east coast (mountainous Virginia), but spread VERY easily when tiny bits of roots are move...Read Mored (as in bulldozer work).
It is very hard to get rid of, too. VERY. 25% glycophosphate helps on cut stems. Applied on foliage, the plant laughs. Those little peices of roots keep expanding to bigger and bigger patches.
This plant stays in it's place. But wherever the place is make sure it has a lot of room. It grows extremely fast. At first I thought it ...Read Moremay be a bit invasive, but it isn't. Just a very fast strong aggressive grower.
I'm marking my experience as "negative" because in the long run it is a non-native and has eventually run amuck. I transplanted one plant...Read More
This plant is not the invasive species! This is a non invasive cultivar I’m searching for years now😁
It does not spread by seed in this part of the east coast (mountainous Virginia), but spread VERY easily when tiny bits of roots are move...Read More
In South Carolina the Japanese Knotweed is listed on their Invasive Plant list as a Severe Threat.
This plant stays in it's place. But wherever the place is make sure it has a lot of room. It grows extremely fast. At first I thought it ...Read More