Japanese knotweed affects homes all over the UK, but what exactly is it and why is it such a nuisance?
What is Japanese Knotweed?
Japanese knotweed is a non-native invasive plant that spreads rapidly, dying back to ground level in winter and growing up to around two meters above ground in the summer months.
We tend to be able to see the plant between late spring and autumn, and it is best treated in summer.
While the plant can grow to over two meters in height above the ground, its roots can grow larger, as much as three meters deep and seven meters wide.
Property Devaluation
Estimates of how much Japanese knotwood can devalue properties by vary, but they tend to reach around 15-20%. Some cases may see the property value only fall by 5%, whilst in cases of severe infestation, the value may plummet more than 20%.
Therefore, it is important to act quickly if you see knotweed in your garden or near your house, preferably by contacting a professional to help eradicate the weed as best possible.
The plant can spread quickly between houses, is hard to completely get rid of, and can exploit any existing weaknesses in buildings. Left untreated, it can block drains, weaken walls, and damage property foundations.
Knotweed that is more than seven meters away from the property boundary tends to be deemed low risk, but if it is discovered within seven meters of the boundary, lenders can see it as a concern, due to its rapid growth.
Some mortgage lenders refuse to lend on properties affected by this weed, but this is not the case for all lenders.
Responsibilities
Since 2013, people selling their homes are required to state whether Japanese knotweed is present on their property using a TA6 form.
Sellers have a responsibility to check their gardens for this weed, and if found, must confirm that their property is affected, where the weed is, and provide a management plan for its eradication from a professional company.
It tends to take at least 3-4 seasons to eradicate Japanese knotweed using weedkiller, but professional contractors have access to more powerful weedkiller which can half this time.
If you do have Japanese knotweed on your property, you don’t legally have to remove it unless it’s causing a nuisance, but you must prevent it from spreading off your land. You can be prosecuted for causing it to spread into the wild.
Who is at Risk of Japanese Knotweed?
Many properties across the UK are now affected by Japanese knotweed.
Your property may be at risk of the plant if it is situated near a:
- Canal
- Footpath
- Carpark
- River
- Stream
- Railway
- Waste ground
- Any other land that has been left unattended for a long time