General Knotweed, mortgages and treatment
How do I know if it is Japanese knotweed?
Start with the stem: hollow like bamboo, flecked purple and bending in a zig-zag at every joint. The leaves are shield-shaped with a flat edge where the stalk joins, and in late summer it throws up sprays of cream flowers. Old brown canes can stand through the whole winter. Sending us a photo is quicker than comparing pictures on your phone.
Is it illegal to have knotweed in my garden?
No, owning land with knotweed on it is not an offence. The law is broken if you let it spread into the wild, and soil or cuttings count as controlled waste. If it moves into a neighbour's garden, they may be entitled to bring a claim against you.
Will knotweed stop me getting a mortgage?
It does not rule one out. Plenty of lenders will go ahead if there is a professional survey, a treatment plan and an insurance-backed guarantee that can pass to the buyer.
How long does treatment take?
Most spraying programmes run for three to five growing seasons, with monitoring afterwards. Digging it out takes days rather than years, but the bill is a good deal higher.
Can I just dig it out myself?
We would not. Small fragments of rhizome regrow, and the soil cannot go in your wheelie bin or be taken to the household waste site.
Does knotweed damage houses?
It pushes into weak spots such as cracks, old drains, paving and lightweight outbuildings. Good foundations are rarely harmed, but a stand close to the building can still knock value off or hold up a sale.
What if it is coming from my neighbour?
Book a survey so the position and direction of travel are recorded. That report is what you show the neighbour, the landlord or whoever owns the plot next door.
Should I cut it back or strim it?
Please do not. Strimming throws fragments about and undoes a spray programme. Leave it standing until someone has looked at it.
What do I have to declare when I sell?
The TA6 form asks the question directly. If knotweed is there, say so and include the management plan. A wrong answer can come back to bite you after completion.
How much does knotweed removal cost?
For a normal garden, a spraying programme typically comes to between £1,000 and £3,000 over its whole run. Digging out costs more because of the soil volume and disposal charges. After the survey you get the figure in writing.
Do you cover all of Stockport?
Yes — Addresses across SK1 to SK8, covering the town centre and every district out to the Peak District edge and the Cheshire borders.
