Euphorbia Blackbird gone green

alfharris8

I have a couple of Euphorbia Blackbird for several years that whilst very healthy looking have lost nearly all of their dark foliage and returned to green. 
They are planted in partial shade and I think I have read that might have made a difference.
Could anyone confirm this and would a sunny site bring out the dark colour again or is it irreversible?

punkdoc

I think E. Blackbird is one that needs some sun to maintain its colour.

alfharris8

@punkdoc
Thank you. Do you know if the darker colour would return if I put it elsewhere?

punkdoc

I think it might. Sorry can't be definite.

alfharris8

Thanks for replying anyway.