Answer: Yours is a pretty risky proposition. Glads bloom according to weather conditions (and maturity). If you delayed planting them so they'd bloom late, they might - or they might grow really fast to make up for the delay in planting, especially if the weather is nice and warm. Glads can take from 70-100 days to bloom. I think that's too much of a spread to be able to count on manipulating their bloom time. But, if you're willing to take the chance, plant at two week intervals, beginning in May.
Good luck with your project!
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