This Japanese Knotweed has been colonised by Convolvulus and I can only say they deserve one another. The pink buds of Convolvulus or bind weed will open shortly into the white saucers we know well but the Japanese Knotweed is more insidious and troublesome.
Recognising Japanese Knotweed
- Japanese knotweed begins growing in early spring and can grow as much as an inch per day reaching a height of 5 feet by May and 15 feet by June.
- It produces fleshy red tinged shoots when it first breaks through the ground.
- The large, oval green leaves have a silver tinge on the underside with clusters of cream flowers towards the end of August.
- Japanese knotweed has a hollow stem, similar to bamboo and forms dense clumps that can be several metres deep.
- Japanese knotweed dies back between September and November leaving dead, brown stems but the rhizomes remain
Problems with Japanese Knotweed
- Knotweed’s stout rhizomes or underground stems, are notorious for pushing through asphalt, building foundations, concrete retaining walls and even drains, causing significant damage.
- Legally you must not allow Japanese Knotweed to spread onto adjacent land or the owner of that land could take legal action against you. Nor can you plant or encourage the spread of Japanese Knotweed including moving contaminated soil from one place to another.
- Chemical control by regular application of herbicide is the only way to eliminate the weed and it may take several years.You need permission from the Environment Agency to use herbicide near a water course.
