I have Wendy's Wish in my front garden. The heat here has been brutal and it is suffering. However, when the monsoon type rains were pounding it, it grew waist high. I bought a 4" pot in spring and it has become a waist high, barrel of a plant. I find the stems are sort of "fleshy," which makes me think it won't last where it is without some protection. I will cut it back severely before the first freeze, and hope for the best.
To answer your question, I personally would leave it in the pot and move it into the ground in spring. Once it gets established, you will have a better idea of whether it will need extra protection over our brief winters. If you decide to move it this year, at least wait until the temps settle into the 80s, at least.
