when out walking the other morning i was enjoying looking at this wild flower which was blooming abundantly. so much so , i decided to add it as background to a painting i am currantly working on of sunflowers. well this evening while painting i could not exactly remember what the center looked like, so i went out to check only to find not a one any where to be blooming. My question, are they a.m. bloomers only? Also wondered if there were any tricks to keeping them open after you cut them? The ones i cut the other day only stayed open about 15 minutes.