flossie/....i might be able to help you a little bit on this but i am not an expert,?..the only places that i have found a bumbles nest apart from under ground is at the base of a old hawthorn hedge in afield just below the grassy overhang and just off the floor ,..it was sited on the north side away from the sun ,..hope this might help.....i can not help you with the latter part of your question because i have never had one but would be very interested in how you get on.......i would site asap ,...i have just seen the smaller brown species in my garden for the first time this year so it may not be too late,..ps just a thought ,if you can catch one why not try and house it in the one you have bought,its worth a try.