dognjo, he's on Eukanuba light which is what GDBA supply for him and hasn't been changed in years.
SophieLeeds, I wouldn;t be so bothered if he took the odd plant but he's not interested in what's growing, just what it's growing in.
Mammyshaz, we took him to the vet who said that it probably wasn't anything much. He did find something in his abdomen which concerned him a bit so he had him in for a day of tests and xrays but that found nothing. However, there was a concern that his urine is too dilute so they have tested it since and still not worried but they are keeping an eye on him as it could be due to something with a long name that I can't remember now.
I have now barricaded the greenhouse so he can't get in there. Of course, it makes it a pain when I want to water the pots. I'm planning on having a lean-to greenhouse fitted for next year and that will have glass doors which should stop him.