Can Japanese Knotweed cause problems when buying and selling property?

Posted on: July 18th, 2016

Japanese Knotweed can cause a number of problems for both buyers and sellers during the course of a property transaction.  Here is a useful guide on how to identify this invasive plant and what implications this can have on you whether you are buying a property or looking to sell.

How to identify Japanese Knotweed

Japanese Knotweed can be identified by its bamboo like shoots which will usually contain purple flecks.  These shoots can grow up to 7ft and will produce branches with shovel shaped leaves.  Flowers will appear in the summer which can reach up to 6 inches in diameter.  Each year the plant will ‘die’ over winter but will reappears in the spring before it begins to flower.

This plant will grow rapidly and can quite easily overwhelm and suffocate other garden plants.  Even though it does not produce seeds it can sprout easily from one small section of the shoots. 

What implications will this have if I am buying a property?

There are a number of points to consider below if you are considering purchasing a property.

The scale of the problem

You will need to establish the scale of the problem from the seller.  As the shoots can be almost invisible during the winter months it can make it difficult to detect on your visit around the property.  The mass of the plant is underground so even if a small section is identified this could lead to a large problem in time.

The seller has an obligation to disclose the existence during the enquiry stage of the property transaction (there is a question contained within the Law Societies ‘Property Information Form’ which is completed in the majority of transactions asking of the presence of this plant).

It is important to also know if the Japanese knotweed has encroached onto the neighbouring property.  If it has, you could be facing a ‘nuisance’ claim if the issue is not resolved.

It is not illegal to have this plant on your garden however if it is not controlled then new legislation can be used to enforce its control which could be costly and time consuming to you.

You can obtain professional advice as to the scale of the problem and it is advisable not to rely on the seller merely ‘sorting out’ the problem.  As you will see below, it can be difficult to remove the plant completely.

Can lending be obtained?

The appearance of Japanese Knotweed could cause difficulties in securing suitable lending.  Some lenders will refuse to lend outright although others will consider lending if they can see that the plant is being eradicated by a professional firm that can provide a guarantee which is backed by insurance and/or a management plan.   A copy of this guarantee and/or plan will need to be sent to the lender during the course of the transaction for their formal confirmation that they are happy to proceed with their lending decision.

Structural Damage

If grown near the property, this plant can easily cause damage to the structural integrity through damage to the external walls or the foundations (the plant can grow very deep underground).  This could be costly and time consuming if rectification works are required to put right the damage or to return the property to a structurally sound state.  This also could affect the ability to obtain lending or to the sell the property in the future if damage is caused as this could reduce the value of the property if substantial works are required.

What do I need to do if I am selling a property?

The most important point to note is that you should not hide the existence of Japanese Knotweed but let your potential buyer know.  Concealment of the existence of this plant could be classified as misleading the buyer and a buyer could have a claim against you.

You will want to consider the removal or control of the plant and there are a number of ways in which you can do this:

  1. Weed killers – there are few types of weed killer that are effective although they usually require multiple applications. You will need to ensure that you read the labels before applying to ensure it is affective against this particular plant (those with Glyphosate are the most effective)
  2. Digging out – you could try to dig out the plant however the shoots will penetrate deeply into the ground which can make it difficult to ensure that you have retrieved all the shoots to avoid any regrowth. You can only dispose of the dug out plant at a licenced landfill site or by destroying the plant on site by burning
  3. Professionals – there are a number of companies will assist in the removal and can provide insurance backed guarantees when required. this is particularly useful when you are selling your property as explained below

Engaging a professional company is most advantageous as a guarantee and or/management plan can be provided to a potential buyer making it easier for them to secure lending against the property.  The first two options may be cheaper but could cause costly rectification if not carried out properly or could prevent guarantees being obtained later down the line if you later find that they are required.

You may also want to ensure that no structural damage has occurred by arranging for a surveyor to come and assess the property so that you are aware of any potential issues that could arise during the course of the property transaction or that could affect the value of the property.

For further visit https://www.rhs.org.uk/advice/profile?pid=218 or contact a member of our Residential Property team.