Sometimes, I'm having a hard time figuring out when the flower is done. Especially flowers with prominent centers. I think the center is not done, but the petals are. Do I cook it some more? I noticed this especially with impatiens and a rose, but not limerock ruby.

Even pressing simple fern foliage (jap painted fern), I couldn't tell what was done. I tried two 30-second spurts. seemed good. Did another 30 seconds. still seemed good. Not sure what the difference was. do I have to go too far and sacrifice the plant to learn the hard way?