In message , Dorry
writes
I have bought an "obediance plant" - (sorry, only name I was given.) -
A friend has told me it can spread uncontrollably like a weed - so i
have put it in a large pot, instead of my border. Can it also spread
easily by seed?


The usual plant that goes by the name of obedient (sic) plant is
Physostegia virginiana. I suspect that it is invasive in the US, rather
than here, but perhaps someone with experience of the plant will chime
in.
--
Stewart Robert Hinsley