Can confirm that root free/runner free nettles
do make a nutritious 'tea' for plants.
Also, ends up disturbingly smelly when you try to get rid of the
immersed, blackened stems.
Probably less of a problem on an allotment,
than along a suburban street.
Why is bocking 14 so much better? I’ve seen green manure vids on yt that suggest nettle and wild comfrey just as good...