I felt bad about killing off my knotweed (Polygonum cuspidatum) last year. It flourished in the sandy soil behind the house and hosted thousands of bees late in the summer when few flowers are left. But it was a runner, spreading uncontrollably. One application of Round-up did it. (Do it when in flower, like for bindweed.) I would like to replace it with a variety that is purely a clumper. Anybody hear of such a knotweed variety? Gerald
Frankly, I would welcome it, if it does come back. I'm already feeling bad about killing a plant I admired so much... Yes, it is a wild one...but I would admire its tenacity and ingenuity to survive. Is nature only 'good' if it fits exactly in the space we have alloted it? I have always loved dandelions too...
Nope! Nature is only good if it fits exactly in the space nature has alloted it . . . which in this case, is somewhere in Japan
It's so fortunate that we didn't stick to Nature's 'allotment' of where she originated wheat, corn, tomatoes, tulips, mints, apples - in fact the whole gamut of grains, vegetables, fruits, herbs, flowers and trees....isn't it? Or should we send all the 'foreigners' home to where they 'belong'? Nature is the expression of a spontaneous creative force that spills out all over and spreads out to where it can, either abetted by or in spite of human conceptions of what should be where and when, as prescribed by our individual and social whims and needs...
Hi Gerald, four things: 1) consider a clumping bamboo instead, they are beautiful, evergreen and almost no maintenance, won't spread out of control and are very commonly available at local garden centers these days. Be sure it's a clumping kind, not a runner unless you are prepared to do some root pruning twice a year or use a barrier to keep it contained. 2) You didn't have you knotweed long enough perhaps to come to loathe and despise it but you would have sooner or later. It's a horrifyingly bad plant out of it's native area mostly because it's so destructive and as close to impossible to get rid of once it's established as triffids. I've heard people tell of having to get in heavy equipment and basically dig up their entire lawn and garden and scrape it away just to get rid of it once it's heavily established. The roots can go down as far as 3 meters deep! 3) Very few people are able to sucessfully kill knotweed with one application of round up, I've heard it's not unusual to take many years to finally get rid of it so don't be surprised if it pops back up in the spring. 4) I know you probably know this already but you posted in the bamboo forum and mentioned runner and clumper all bamboo related terms. Many people confused knotweed with bamboo and add to the entirely undeserved reputation of bamboo as an invasive hard to control plant. I just want to state for the record that bamboo and knotweed / "mexican bamboo" as it's also known by is entirely unrelated to bamboo. Bamboo is an evergreen unlike knotweed. Even the most voracious running varieties of bamboo are extremely easy to control compared to knotweed.
(Sorry if I posted in the wrong section. I'm still learning how to use this site.) I certainly won't promote the planting of wild knotweed. (Though I wouldn't get excited by the fact that its roots go 3 meters deep; for example, alfalfa roots go 10 meters deep.) Definitely, the wild stuff seems extremely difficult to control. I now suspect that the one I killed was actually a domesticated one - Giant Fleece? - which seems to be only mildly invasive. Whatever it was, I would classify it as a 'loose clumper.' New shoots came up several inches from the old ones. Besides that, it was growing on the north side of the house, making it weaker than normal since knotweed really appreciates strong sun. But a true clumping variety like Persicaria japonica var. Crimson Beauty, besides being beautiful, is a very different plant. The stems are tight up against each other. Have you seen it? http://msuplants.com/pd.asp?pid=1508
Cardina is right, Its the most evil weed thats out there. Here its more a hedgerow weed and we try to get rid but it just keeps on coming back. If someone finds it in their garden and does'nt try to remove they are fined. Its such a vicious spreading weed. The only way I would think a way to get rid is to get spading/forking right down to your house footings, dig it out or cement the weed in never to be seen again. I watched a programe recently and she bought a house without looking round it, I believe she bought it at an auction. Anyway when she finally saw the garden every square inch was covered in knotweed and she had to dig out every crumb of soil to get rid of the weed. Gives you some idea how rampant knotweed is. Gardeners World Web site and spring is when you destroy. READ More Here: http://www.gardenersworld.com/how-to/problem-solving/weeds-japanese-knotweed/ My problem soon will be this menace: http://www.gardenersworld.com/how-to/problem-solving/weeds-bindweed-field/ Every week I have to release my plants from the grip of this weed...arge...
Why are all knotweed species demonized in the popular literature? Partly because of the confusion in the taxonomy system. Canadian taxonomists put all the knotweeds together under the name of one species: Polygonum cuspidatum. If we look further afield to other countries, we'll find knotweed species listed under 6 more different Geni: Reynoutria, Fallopia, Persicaria, Pleuropterus, Tiniaria and even Pleuropterus. If we study deeper into the genetics, we'll discover that within the different species and sub-species, there are four different levels of polyploidy: diploid, tetraploid, hexaploid and even octaploid. The variation between species and strains is incredible. Nobody seems to have a handle on it... In Canada we are stuck with only one name for all of them, as though they were all the same plant...thus the confusion and total demonization of this incredible plant. (Please note: I am not suggesting that anybody consider any other strain than "Crimson Beauty". Even Giant Fleece (polymorpha), though only moderately invasive, needs some attention to make sure it doesn't take over. Left to its own devices, it will spread. And I, being a lazy gardener - more attuned to enjoying nature's wonders with a cold one than cultivating her - decided to change over to Crimson Beauty...)
You have four choices for dealing with knotweed: 1. Stop the damage it does to our asphalt and concrete infrastructure and its invasion of native species sites. Kill it with Tordon 22K. (Available in Canada as Tordon 22K; active ingredient Picloram) This herbicide is much much more effective than Round-up. Is supposed to kill it with 2 sprays. http://www.guardian.co.uk/environment/2009/jan/06/wildlife-travelandtransport 2. Use it for medicine: Knotweed is grown commercially in China to produce resveratrol. http://www.traderscity.com/board/pr...iant-knotweed-extract-resveratrol-10-99-8633/ 3. Eat the young shoots. A few people say it tastes something between rhubarb and asparagus. http://www.wildmanstevebrill.com/Plants.Folder/Knotweed.html 4. Reduce your carbon footprint by using it for fuel. It is more efficient than any other plant in fixing atmospheric CO2. Knotweed is, by far, the highest producer of biomass/acre compared to any other plant tested in the temperate zone. Perhaps knotweed is Nature's response to our polluting her atmosphere with CO2? http://stary.biom.cz/clen/vp/seven_ang.html