Japanese knotweed (Fallopia japonica) is a weed that spreads rapidly. In winter the plant dies back to ground level but by early summer the bamboo-like stems emerge from rhizomes deep underground to shoot to over 2.1m (7ft), suppressing all other plant growth. Eradication requires determination as it is very hard to remove by hand or eradicate with chemicals. New legislation now covers its control – see below.
Leaves are heart or shovel-shaped and up to 14cm (5½in) in length and borne alternately (in a zig zag pattern) along the stems.
The creamy-white flower tassels produced in late summer and early autumn reach up to 15cm (6in).
This plant occurs in a wide variety of habitats, in many soil types, and a range of moisture conditions. It appears to be found primarily in disturbed open areas with plenty of sun; shade depresses its growth. Edges of roadways and streambanks are common locations at which to find Japanese Knotweed.
When tackling Japanese knotweed, cultural control methods pose some problems.
On no account should Japanese knotweed be included with normal household waste or put out in green waste collection schemes.
If using chemical control, it usually takes at least three to four seasons to eradicate Japanese knotweed using weedkiller. Professional contractors, however, will have access to more powerful weedkiller that may reduce this period by half.
When using weedkiller, always follow the instructions on the pack to make effective and economic use of the product while minimising risks to people and the environment. For home gardeners, perhaps the most effective and simplest method to tackle Japanese knotweed is with a glyphosate-based weedkiller.
Some of the most important health benefits of Japanese knotweed include its ability to prevent and treat cognitive disorders, improve heart health, lower your risk of cancer, reduce gastrointestinal distress, lower blood pressure, maintain proper insulin levels, and many other unique benefits.