Deal with Japanese knotweed on or near your property

This guide is for UK homeowners and buyers who have found, or suspect, Japanese knotweed in their garden or right next to it. Knotweed rarely harms a sound house, but it can complicate mortgages, sales and neighbour relations, and mishandling it can break the law and spread it further. You will confirm what you have, stop accidental spread, choose a treatment that suits your plans for the property and handle the paperwork that buyers and lenders ask for. At the end you will have a site record, specialist quotes you can compare and a clear plan through to the end of the guarantee.

What is inside

• Full step-by-step method8 detailed steps with decision points
• Ready-to-use templatesLetter to a neighbour or landowner about encroaching knotweed · Request for quotes from knotweed specialists · Knotweed site record
• Timed action plan7 stages from “Day 1” to “Before selling or remortgaging”
• Costly mistakes to avoid4 traps and what to do instead
• Complete checklist11 items to tick off
• Insider tips and fixes4 tips and 4 common problems solved

Step by step

1. Confirm it really is Japanese knotweed

   Look for hollow, bamboo-like stems with purple speckles, growing in a zigzag from one leaf to the next, and shield or heart-shaped leaves with a flat base. In spring, red or purple asparagus-like shoots appear; in late summer and early autumn it has creamy-white flower tassels; in winter it dies back to brown, hollow canes that stay standing. Common lookalikes include bindweed, Russian vine, Himalayan balsam, bamboo and some dogwoods, so check every feature, not just one. Photograph the whole stand, a stem close up, a leaf against your hand and the base of the plant, with a tape measure in some shots. If you are still unsure, send the photos to a specialist identification service offered by many knotweed firms or check your council's guidance before paying for treatment. Do not dig up a sample to show anyone.