This is a tier that takes the most time and resources. Not only is it big in size and all but the petals do take a heck of a long time to make. I lost count after the first three hours and I really think I like petals in thousands.
I used a mix of 50/50 for the petal ruffles, and I let the ruffles dry for 15 minutes.
Because of the high humidity, I found the ruffles were still quite soft. If I had to do these ruffles again in summer I would use all gumpaste and I would leave them to dry longer. So depending on the weather you may want to take that into consideration.