What type of hydrangea requires the least amount of sun and how many hours would that be. Thank you.
Ottawa, Canada. Zone 5. garden faces south west and has a big pine tree in front of it.
Certified GKH Gardening Expert
You, actually, have several choices here! I would recommend the climbing hydrangea, myself. These seem to be the most shade tolerant of all of them, and in fact, full sun seems to bother them.
At this rate, it will not be how many hours of direct sun you will worry about. Just that it gets bright filtered light almost all day. This will fit your location perfectly, it would seem.
This article will help: https://www.gardeningknowhow.com/garden-how-to/gardening-by-zone/zone-5/zone-5-hydrangeas.htm