For me and bloom times, it it all about spring. How late we get snow in April or May, and then how quickly it warms up.
I am recording my bloom times. It is somewhat a tedious task, as I go through all the individual pictures and from there I gather the bloom times. I don't go through the garden and write down every single iris when it blooms, but later, I go through the pictures. Some have a repeat bloom, though not necessarily a rebloomer. Like some bloom in May, then later in June. And some bloom off and on almost continuously. (And, of course, some don't bloom!)
My Zone 8 is based on the lowest winter temperature, but my bloom season is much later than others in Zone 8. Sometimes spring is colder than winter, but not usually, but most often the winter chill is still in the air.
