You have peony in zone 9....10.....that's a surprise to me, I thought peony had to have a winter.

Anyway, where we are peony just naturally dies back and returns in the spring when soil temperatures rise.
In your tropics I have no idea since I didn't know that peony was viable.

I suggest you get in touch with the American Peony Society.....or one of your local Society chapters---they should be able to give you the best, up-to-date info.

Mine are all yellow now and ready to cut back. I will use a hedge trimmer to cut them to about 4 inches off the ground. Keep the weeds from taking over during the winter. I do not mulch over the plants, as it insulates from the needed cold, and could cause them to not bloom next year. Peony will do well in your location as long as they are not too deep, and get enough winter chill. Al

Or you could call your State Horticulturist.

Hello msteve47,

What varieties do you have? And are they planted in full sun? Are they planted with the crown exposed?