What is the advice on adding brambles and nettles to compost heaps?
Should a compost heap be kept dry (covered), or should it be 'watered' occasionally?
I'd cover the contents with a sheet of polythene, to stop it drying out, and then a layer of sacking or old carpet on top to keep the heat in.
Brambles and nettles are fine to add, in my experience, but I'd certainly try to chop the brambles up first, even secateurs are fine, cut them into about 6" lengths.
Do not put nettle roots or seeds in as they can survive in homemade compost so you could end up spreading them around you garden
IMHO nettle roots are bright yellow and are easily removed and chucked back into the newer heap.
Each to his own and I'm certainly not telling anyone what to do, but I chuck the whole lot in mine, roots, seed heads the lot. If the heap gets hot enough, they'll all die. If it doesn't get hot enough, it's not being done properly.
Non flowering nettles are ok, and the only trouble with brambles is the thorns persist and can be equally uncomfortable as fresh brambles.