Thinking about it, the last time I went to the botanical gardens in brum the tea shop had expanded into an art gallery where local artists were displaying work with £100 - £5000 price tags attached.

Might be worth visiting all the local RHS/English Heritage/PlacesThatToffsLikeToGo sites see if they have similar facilities for local artists or if they would be interested in displaying your work for a cut of course...