Invasive Plants

Non-native Invasive plant species are more than just an annoyance, these weeds can do structural damage to your home causing its value to plummet.

The most prolific invasive species in the UK include plants such as:

  • Japanese knotweed
  • Giant hogweed
  • Himalayan balsam
  • Rhododendron ponticum
  • New Zealand pigmyweed (this is banned from sale)

Laws, such as the Weeds Act 1959 and the Environmental Protection (Duty of Care) Regulations 1991 are designed to help control the spread of certain invasive plants such as Japanese Knotweed.  Although for most of these invasive species it is not an offence to have them on your land, but it is an offence to enable it to spread outside the site boundaries.

Japanese Knotweed originally from eastern Asia, was first introduced to Great Britain by the Victorians in 1886 as an ornamental garden plant.

It is now widely established across most of Great Britain and is notorious for forming dense stands which are extremely hard to control. This makes it one of the most frustrating invasive species in the UK because it would be virtually impossible to fully eradicate it. It is estimated that the Japanese knotweed costs the economy £166 million a year.

Japanese Knotweed is a highly invasive plant that has received a considerable amount of negative press over the past decade.

The plant’s roots can cause considerable damage to property. As a result, its existence is of concern to home buyers and mortgage lenders.

These are some of the problems that have arisen:

  • Damage and blockage to drains and other buried services
  • Collapse of boundary or garden walls
  • Buckling and other damage to drives, patio and similar paved areas
  • Damage to the foundations of conservatories, outbuildings and even house foundations (especially older properties which often have much shallower foundations than modern homes.)

There are also other consequences for property buyers if Japanese Knotweed is growing on the property. Mortgage lenders may refuse to lend if the plant is known to be growing on the property or may retain part of the advance until it has been properly eradicated.

Find out your lender’s position as early as possible, you can check online. Lenders publish their lending requirements in the Council of Mortgage Lenders (CML) handbook. Japanese Knotweed is addressed in the Part 2 section.

It is also likely that any damage to buildings and drains will not be covered by buildings insurance.

There are also some potential legal consequences as it’s a criminal offence under the Wildlife and Countryside Act 1981 to knowingly allow Knotweed to spread from your property.

Furthermore the ‘Anti-Social Behaviour, Crime and Policing Act 2014’ provides that community protection notices can be used to force landowners to control non-native invasive plants (which includes Knotweed) on their property. Fines can be imposed for non-compliance with such notices.

Key steps if you discover knotweed at or near your home:
  • Speak to your neighbours immediately.If the plant has spread to or from their land then any treatment you carry out solely on your property will be a waste of time as the plant must be killed in its entirety. Your neighbour will likely be happy to share the cost of the treatment.
  • Get a PCA Certified company to carry out an immediate inspection to confirm that the plant is in fact Knotweed.
  • Ask for a treatment plan proposal from 2 or 3 companies– costs vary considerably.
  • Make sure that a suitable 10-year insurance backed guaranteeand indemnity policy will be issued upon completion of the plan. It is critical that this policy is accepted by all major UK lenders, if it isn’t speak to another company.
  • If you are about to go on the market be prepared to pay for the treatment, in its entirety, up front. Often the lender insists that the plan is paid for up front as the subsequent owner may not pay for the treatment once they move in and the lenders security will be compromised.
  • Don’t ignore it– the problem won’t go away
  • Don’t attempt to remove it yourself. Knotweed is a notifiable plant and disposing of it through non-formal procedures can incur a fine of up to £2,500 and even earn you an ASBO!
  • Don’t cut it, trim it or prune it in any way and don’t disturb the soil around or anywhere near the plant.
  • Don’t cut the grass or any other vegetation near the plant.
  • Don’t spray it with weed killer  There is more to killing it that simply spraying Roundup. A professional will know the best application method, timing, treatment intervals etc.
Take control

Taking control of the situation is paramount. The above advice should put you well ahead of the curve when it comes to selling your home and hopefully avert any lender issues that might otherwise stop your sale going through.