I grow it outside year round, but of course I'm in Florida, in good draining potting soil. My mom and sister have this plant too and live in New Jersey. They summer it outdoors and then bring it in when it starts getting chilly. It seems to need a little cold weather (but not frost) to bloom.
My sister's bloomed in October/November this year after bringing it in. In Florida, we don't get a cold spell until later in the season.
After it blooms, new little "pups" grow from the base of each plant. Once bloomed, it won't bloom again on the same plant. I usually wait until the pups get bigger and repot just those so it has a nice bloom the next year.
Sue, I don't know. I have some other broms too, and I'm waiting to see what happens with the pups on them.
I had read a book from the library on broms and it stated that some pups take several years before they bloom again. Tillandsia (sp?) being one of them.
This particular billbergia, we have had in our family for years. Actually, my mother mailed me three shoots from N.J. in the mail about 5 years ago, and that's how I got it here.
I've got a pot of them of a similar size to yours. It really needs to get to a good sized clump like to shake off its straggly appearance but when it does it's a great looking plant. Very cold tolerant for a brom. Mine gets temps down to 0oC (protected from frost) without an issue.