We have been going and doing the plant fair at Longstock every year for over 20 years but its never open on Plant sale day as they restrict numbers and its always been a ticketed entrance - so we took the opportunity on our way up to Wisley to book and call in.
As a bonus the new cafe is very good and reasonably priced as is the nursery there (Compared very favourably to Wisley plant centre!)
It is one of the Camellia relatives; in the family Theaceae.
My best first guess is a Stewartia and I can find a reference for Stewartia pseudocamellia growing at Longstock but I wouldn't be surprised if they have others too.
I think Polyspora and Gordonia have thicker leaves?
Thanks for the pictures Charlie. It is many years since we went there, I had forgotten how beautiful and peaceful it is. You did well to get pictures with no others visitors in the frame or were you blessed with the place to yourselves?
We were the first in at 1300, it had got busier by the time we left, it takes a surprisingly long time to get around all the paths and routes to make sure you dont miss anything.
As we were a bit early when we arrived we headed for the newly built much larger cafe, I am happy to report it was very good and not over priced, the nursery was good although a bit less so than I remember (but a lot better than the Wisley plant centre)
We find Longstock not a bad place to stop for a break if heading up the A303!