I just purchased a 2 gallon Endless Summer. Can I plant this in a raised garden bed? Or a pot and what size?

Congratulations, you’ll love your Endless Summer^® hydrangeas! You can definitely plant your hydrangea in a raised bed or a decorative pot. Since you’re in Arizona and planting in zone 9b, a container might be a great option for your first season to see where they perform best. Be sure to shade the plants from the hot afternoon summer sun to keep them healthy. Keep the soil moist, but not wet and you’ll be in great shape. Here’s a video for information on planting in a pot: https://www.youtube.com/watch?v=pvKcieDfDcE.