Posted: 17/04/2014 at 19:31
But both are lovely when they flower and so good for insects - I'd let them flower then cut them down. Some more may spring up next year, they'll look lovely when in flower too but you can cut them down afterwards. Both are also good food for pet rabbits or dairy goats, so if you know anyone who keeps either, when you cut them down take them along.
http://www.wildlifetrusts.org/species/cow-parsley I've sowed this in my Little Wilderness at the back of the wildlife pond, and isn't this hogweed flower gorgeous?
In the autumn you can make homes for insects out of their hollow stems.