Maybe you could try sucessive planting. Start some in pots early and then plant them in the ground. Then stagger your other plantings say a week or two apart and you are bound to catch some in bloom at the right time.

I started some in pots and they were about a foot tall when I put them in the ground and then I planted some at the same time as sprouted tubers and some that just the eyes were started. Maybe this would work for you to stretch out your bloom times. Just a thought