Paperbush/seed Or Plant?
Best time to plant a \\\"paperbush\\\" bush plant from seed,
Certified GKH Gardening Expert
You will want to do this after all threat of frost has passed. It is best to start these indoors under bright lighting to give it a better chance of survival.
Since you are on the edge of this shrub's hardiness zone, it may need extra protection in the winter.
Here is an article that will help: https://www.gardeningknowhow.com/ornamental/shrubs/paperbush/paperbush-plant-care.htm