The wild ones grow here in dirt road ditches where it is moist. I have transplanted some in my yard to very rocky soil not clay. They do well here and smell good when they bloom. I don't know about clay soil. I think my soil is acid though.

I threw out seed from wild ones that I made jelly from.I have a small grove of them behind our pump house in clay soil.The flowers are pretty and smell lovely.They make good jelly or syrup and the birds eat them.They also planted poison ivy in them!I think they need some shade-mine are on the east side of the pumphouse.There are also some pretty new varieties with purple leaves.Posy Pet

It is an invasive plant...sends up sprouts from the roots and makes a thicket, so make sure it is not too near your garden or flower beds. The purchased kind is just as invasive as the native...that's what I have. We built a chicken yard around it to keep it under control. Chickens loved the shade.

My mother still talks about the elderberry wine her grandmother made. Ever tried making any?
I've never had any but am tempted to plant some trees and try.
KK

Made wine last year. Do not need much juice. It is some potent stuff.