General Knotweed, mortgages and treatment
How do I know if it is Japanese knotweed?
Start with the stems. They are hollow, rather like bamboo, flecked with purple and kink at every joint. The leaves are shield-shaped with a flat edge where the stalk joins. In late summer there are creamy flower sprays, and in winter the dead canes stay up, brown and brittle. The quickest route is to send us a photo.
Is it illegal to have knotweed in my garden?
No, simply having it is not against the law. Allowing it to spread into the wild is an offence, and anything you cut or dig counts as controlled waste. If it passes onto a neighbour's land, a claim against you is possible.
Will knotweed stop me getting a mortgage?
It does not automatically rule you out. Lenders commonly proceed once there is a professional survey, a management plan and an insurance-backed guarantee that can pass to a buyer.
How long does treatment take?
A spraying programme normally runs for three to five growing seasons, with checks afterwards. Excavation is done in days, though it comes at a higher price.
Can I just dig it out myself?
We would not advise it. Small pieces of rhizome are enough to regrow, and the soil cannot simply go in a skip or the garden waste bin.
Does knotweed damage houses?
It finds its way into cracks, drains, paving and flimsy outbuildings. Solid foundations are seldom harmed, but a stand close to a house can still hold up a sale or lower a valuation.
What if it is coming from my neighbour?
Get a survey done so the position and the direction of spread are written down. That record is what you show the neighbour, their landlord or the land owner.
Should I cut it back or strim it?
No. Strimming throws fragments around and undoes any spraying. Hold off until someone has assessed it.
What do I have to declare when I sell?
The TA6 asks you straight out. If knotweed is present, say so and include the management plan. An incorrect answer can come back on you after completion.
How much does knotweed removal cost?
Spraying a typical garden often adds up to between £1,000 and £3,000 across the programme. Digging out costs more because of the soil and its disposal. Whatever the route, you get the price in writing after the survey.
Do you cover all of Northwich?
Yes — Covering the CW8 and CW9 postcodes: Northwich town centre, Hartford, Davenham, Barnton, Winnington, Wincham, Rudheath, Lostock Gralam and Weaverham.
