Pretty much all herbaceous peonies benefit from full sun--6 to 8 hours a day. They can survive and look pretty good on less, they'll just be a bit leggier and won't bloom quite as well. They will die out if they're in too much shade. Some shade is good though, especially in hotter weather while blooming (can extend the bloom time and keep the darker blooms from fading as much) and there are some varieties and species types that actually prefer more shade. Karl is one of the varieties that does benefit from more sun and support for the blooms. It's a beautiful peony, though! You'll really enjoy the blooms!

Thanks. I thought it seemed odd that different varieties of the same plant would have different light requrements so thought I would ask. I have I believe a Sandra Berhard out front and have been thinking well do I plant this one out back near the woods so it gets mixed light depending on the time of day? I can't think of anywhere that only gets morning light in my yard.

My established peony, bought from Lowes a few years ago if that helps narrow down the type.

It looks like it's really happy where it is! Beautiful peony! Mixed light is not a bad thing, especially if it's because of trees that aren't leafed out yet over winter and in the peony's early/mid growing season with more shade at or after blooming.

It is except for all the rain we've had lately. It is starting to get black spots on the leaves.