Black currants are not their happiest in your heat but I think they will do OK. I am a bit hotter and I find planting them in afternoon shade is a big help. You may end up wanting to erect some shade barriers. I would devote a small patch to planting every variety you can get your hands on, because there may be one which greatly prefers your climate. The birds like them a lot, similar to blackberries I would say. Hopefully kiwinut will see this topic, he is in your area and is growing currants.

Scott

I'm not sure that Ben Lomand is a good choice for commercial production in your area. It is at least partially susceptible to white pine blister rust and mildews. However, unlike NC, there are no restrictions on ribes in TN, so it can't be ruled out. The summer heat in northeast TN is much less than here near Nashville due to the elevation, and currants and gooseberries do quite well there. I suggest you contact Richard Moyer at King College in Bristol before making such a large investment, as he has grown many different currants, for many years, and can probably give you a good idea of the ones that do best in your area (and the ones to avoid), and also give you some idea of the potential for commercial production. If you need his contact info, email me privately.

~kiwinut