Hi, I live in zone 9 in California. Mine was planted around June 1 this year, in a nicely amended hole. It had plenty of good stuff in that hole!
It just sat there for around a month even in this warm weather with lots of water.
Finally after one whole month of being in the ground and having no growth, I got frustrated so I added combined slow and quick release granules (10-10-10) and mulched it heavily with 3 or 4 inches of a blend of small wood shavings and horse manure. It really surprised me by quickly growing out lots of new growth and very soon after, many beautiful lucious blooms.
I was apprehensively watching and hoping I hadn't burned Cherry Parfait and hadn't, but if anyone tries this please be careful, too much fertilizer can burn or kill a plant.
I got the wood shavings and horse manure, which is combined, from a local horse ranch, and it's clean, no seeds!