Originally Posted by peterentwistle
Yeah, like Drone said, to grow blue java you'll need to buy a pup from a reputable seller. Unfortunately here in the UK, our options are very limited for named varieties of banana plants. If anyone is listing blue java seeds for sale, its a scam, at best they will be a seeded wild species of banana like Musa sikkimensis, Musa velutina etc, but it might not even turn out to be a banana seed at all, there are a lot of dodgy sellers out there.
I've purchased blue java pups before, but I can't be certain they were the real blue java, as they often get mixed up with namwah and getting one to flower and fruit here without a large heated greenhouse will be basically impossible. The first one I got several years ago was from a seller in Germany who I believe is a member on here, but he doesn't ship to the UK after Brexit as it's a lot more expensive and a lot of extra paperwork involved. And the other one I got was from turn-it-tropical.co.uk, again not sure if it actually was the real blue java. Unfortunately, I have since lost both of those plants. Canarius have it on their website at the moment (based in Tenerife), I haven't bought blue java from them, but I have bought many other varieties from them over the years, and they seem to be pretty reliable with their banana labelling.
If you want an edible variety of banana that will grow reasonably well here in summer (albeit way slower than in a hot summer climate), then I'd recommend Dwarf Orinoco, Rajapuri, Tall Orinoco and Manzano, all of those 4 I grew last year in the ground in my garden and they seemed to handle the cooler night temperatures we get here. You can see some of them in videos on my youtube channel. Of course, they will need to be brought inside for winter or wrapped up like what people do with Musa basjoo. I'd recommend digging them up and storing them somewhere cool, but not freezing.