Posted 1st Nov 2017 by Peter Byrne
This time of year, the Japanese knotweed's growing season will draw to a close, with the plant dying away
However, specialists Environet are urging homeowners to avoid putting off tackling the weed, as it remains very much alive, as it will only emerge bigger and stronger with new shoots in March.
It will stay standing, but the bamboo-like canes will now be turning brown and brittle, fooling homeowners into thinking the plant has died or that their own efforts, be it through cutting the plant back, or burning it, have proved successful. However, like many plants, the rhizome system beneath the ground is healthy, and will lie dormant during the colder winter months.
Herbicide treatments cannot be used during winter, as they require the plant to be in leaf, but that doesn't treatment will need postponing until spring. In fact, it can be treated throughout the year, with environmentally friendly treatments such as Resi-Dig-Out method - this involves digging out the rhizome roots and sifting out every viable piece before you return the clean soil to the ground.
Homebuyers should be especially vigilant when viewing properties during the winter months - property owners can take advantage of the plant's apparent demise in order to conceal it. The canes will often have been removed but the crown is still visible in the ground, or, in extreme cases, membranes will be laid horizontally in the ground to conceal knotweed, with a path or lawn laid over it.
Nic Seal, MD and Founder of Environet comments: "Each winter we see enquiry levels fall, but we know Japanese knotweed hasn’t magically disappeared, it’s simply a case of out of sight, out of mind. Savvy homeowners will take action through the autumn and winter to tackle knotweed on their land, ensuring they don’t face an even bigger problem next spring. Digging knotweed out of the soil is an instant solution, giving homeowners complete peace of mind and the freedom to sell their property if they so wish."
Identifying Japanese knotweed in Winter
As the temperature drops, the green heart shaped leaves will turn brown and fall from the plant.
In late November/early December the hollow, bamboo-like canes will turn brown and die, although they remain standing.
In March, red or purple asparagus type shoots will appear, quickly turning into green bamboo-like stems which grow at a rapid rate, reaching up to 3m in height.