The best way to treat Japanese knotweed and other invasive plants
Unless you’re unlucky enough to have it growing on your garden — or know someone else who has it — it’s not a plant that includes in lots of glossy picture spreads.
Our general national ignorance was uncovered in a survey by the net garden shop GardeningExpress.co.uk, which found that greater than half us actually quite liked the look of the quick-growing plant’s heart-shaped leaves and creamy white flowers.
That’s hardly surprising, because it was introduced by the pioneering gardeners as an exotic looking ornamental plant in much the identical way that they introduced rhododendrons, camellias and magnolias.
Of course, some rhododendrons had been consigned to the horticultural sin bin, too, but there are dozens of different invasive plants we should always even be on our guard against.
Giant hogweed (Heracleum mantegazzianum), for example, is described as harmful to human health by the Government’s Department of Environment, Food and Rural Affairs.
Himalayan balsam (Impatiens glendulifera) is another no-no, and other invasive plants include floating pennywort (Hydocotyle ranuncluloides), a well-liked water plant it truly is often labeled incorrectly because the native British marsh pennywort.
Floating pennywort is now taking up lakes and ponds in South East England and is heading west to the Midlands and Wales, literally choking native water plants and wildlife since it grows on the rate of as much as 8ins (20cm) an afternoon.
It could be illegal to sell floating pennywort from April this year, and other banned plants include parrot’s-feather (Myriophyllum aquaticum), floating water primroses (Ludwigia spp) water fern (Azolla filiculoides) and New Zealand pigmyweed (Crassula helmsii) that’s also called Australian stonecrop.
Japanese knotweed (Fallopia japonica) can grow as much as four metres high in exactly 10 weeks, and now’s the time to identify whether you’ve it growing to your garden.
The bamboo-like plant is a rhizome which may spread from the smallest root cutting, so in case you dig up the emerging red shoots now you should destroy them as opposed to just binning them or they may just finally end up growing elsewhere.
Alternatively, wait until the leaves are out and spray them with glyphosate (there are several branded versions). Another dose it will likely be necessary in the summertime.
Of course, chances are you’ll like your Japanese knotweed and never wish to kill it off; in spite of everything it’s quite pretty.
But so as to sell your house it will possibly dispose of buyers, with some mortgage providers taking an extremely strong view against it.
And if it strays right into a neighbour’s garden it could cause a variation at the suburban hedge row.
For advice on the best way to remove Japanese knotweed visit www.environment-agency.gov.uk and click the house and leisure icon then wildlife and conservation.
Himalayan balsam need to be decrease before it sets seed, then completely dug out or it’s going to regenerate, while extra care must be eager about the large giant hogweed.
It will cause nasty skin blisters if the sap comes into the contact with skin and just brushing against the leaves, or another component of the plant, may cause rashes, high temperatures, inflammation and dermatitis.
The best strategy to tackle these plants is with glyphosphate when the brand new shoots first appear as rosettes in April or May.
I’ve got to confess, though: I a bit like it.