Do they take time to establish before blooming?

Yes Bearded Irises often take a year to establish themselves enough to bloom.

What is a good fertilizer regimen for them?

I only fertilize mine 6 weeks before bloom time~~So someone else maybe better qualified to answer that question. I use 6 12 12 I think..If they are re bloomers then I give them a dose after spring bloom.

When should I cut back the foliage?
There are two camps to this one. Some don't ever cut back the foliage unless it is unhealthy and dying. Others cut it back in the fall. I have done it both ways and haven't noticed any difference in bloom. So now I dont cut back at all unless it it dying or diseased.

littlebit

Careful on the fertilizer...they don't like nitrogen at all...

If you can find it, give them a tablespoon of super phosphate sprinkled around the clump. Make sure they get full sun.