In message , JennyC
writes

But seriously people - I've never EVER had any seedlings from my
buddleias. So 'crotte de taureau' spring to mind ;o)

I hate people who do this, but - me neither !

Buddleias germinate freely on dry stony ground, but when we had a large
garden on heavy clay, they only ever germinated on the patches where
bonfires had been.
Those patches would have extra potash, but they were also dryer because
of the surface clay getting fired to something bricklike.

--
Sue ]