You are allowed to cut off any foliage which hangs over on your side because that trespasses. However you are not allowed to keep the pieces, because they belong to the neighbour although he might not be very happy if you simply dump them over the hedge.
If you are not capable of or simply do not want to be troubled with doing this, you are entitled to ask the neighbour to cut this at his own expense. If the neighbour refuses, you are entitled to get the work done yourself and seek the costs from the neighbour. If the neighbour will not pay the costs then unfortunately, you are faced with taking him to court firstly to get the costs of the job recovered from him and secondly to get an order to compel him to trim the hedge in future.
Can I clarify anything for you?
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