Postby Needcoffeenow » Tue Aug 29, 2017 8:48 am
We have a lot of experience in dealing with this in our area. If buying, suggest vendor gets professional treatment company who will treat your prospective purchase and any neighbouring ones and (should) give each proerty 10 year insurance certuficate. But if you find some on your property, we suggest treating it yourself before calling in costly pros as they are likely to charge up to £4K for doing exactly what you can do yourself with some Roundup from the garden centre. They also always talk about injecting stems, which is complete bollocks said to impress punters as it makes no difference whatsoever. Knotweed needs to be treated systemically, ie poison needs to be taken down into roots from leaf surface. Now is the time of year to do it. Pick a non-sunny, still, dry day and spray leaves with Roundup or any glyphosate based weedkiller. Spray under leaves too. Leave 3-4 days and repeat. Then do nothing. In around 10 days the leaves will go yellowish with black spots. If any comes up following year, wait until late summer/early autumn (after flowering is best) and repeat. We have effectively killed huge swathes of Knotweed this way. But you ideally need to get neighbours/residents' assocs together to be vigilant and keep it under control as it tends to keep coming. We live near river and it is carried along water courses. NB causing it to apread through cutting or inappropriate treatment is a criminal offence.
