Gladioli bulbs

They want warm soil and must stay frost free, so bit early really. If you have lots?? you might pot some up to start them off, then they will flower earlier than the others to spread the flowering period.

Yes, they need digging up for the winter. You can leave them in the ground, most years they will be fine, but cold wet heavy soil may well cause them to rot, and they may be slow to start nest year, so flower later (which may not be a problem of course).  You'll get lots of little pea-sized babies, which you can plant in a nursery bed (if you like!!) and will create flowering plants in a couple of years time.

Ours were left in the ground over winter, they are happy enough and keep coming back, we've moved them last month tho, to the front garden this year.

I am further south tho so maybe can get away with it.