Question: The blooms on a few of my varieties, ‘Irish Flirt’ and ‘Rob’s Denim Demon’, to name two, don’t want to open fully. Any reason why?
Answer: This was a phone call that we received from a customer. Since the plants were being grown during the summer months, we asked whether she considered her growing conditions to be very warm–she said they were. This is the most likely explanation for the small flowers. Many kinds of stress, high temperatures (say, above 80f degrees for a prolonged period) in particular, can cause blooms to be small or not fully open. This can be more of a problem for some varieties, too. Varieties with very double, frilled, or green flowers often have this trait. Though both of the varieties mentioned are among our favorites, they do, sometimes, behave this way.