In article , Nick Maclaren
writes

There are, indeed, several species in the UK.

Only two, AFAIK, unless you are going to count the wall pellitories
which are the same family but not the same genus.

The annual nettle
(Urica urens) spreads by seed alone, but the ubiquitous stinging
nettle (U. dioecia)

Urtica dioica

spreads by both runners and seed. My remark
applies to both, and I can assure you that the stinging nettle
grows readily from seed and that its seeds are durable (i.e. will
survive a fair amount of composting).


--
Kay
"Do not insult the crocodile until you have crossed the river"