No advice from me on how to stop it from bolting. We use a lot in salads,
and so do several plantings. I've still got about a kg of seed frozen from
last year, in spite of using it at nearly every opportunity...

You freeze coriander seed? That's a new one on me. I found it stays pretty
viable for planting if I keep it in a paper bag. For cooking, I doubt it's
lose much aroma at the rate you seem to use it.

--
Tim C.