Thank you for that very interesting link Mumsy. My instincts are screaming no and all the information I am trawling through is reinforcing that.
I have been to a pain clinic cornergran and am quite happy with what I am currently using but a new (to me)GP seems to have other ideas. 
Do you get emotionally attached to the plants in your garden ?
Only 50% of middle age adult manage more than 1 brisk 10 min walk a month.


