Mystery plant

One of the reasons I love Elford Hall Gardens is the magnificent skill of those who lovingly tend the plants. The buddleias I had two years ao, fro their plant stall, are just amazing. Strong, healthy and butterfly magnets.

When I called in a couple of days ago, I bought a couple more interesting looking young plants.  They price them very reasonably and I have high hopes.

But I’ve lost the label from this one.

Any ideas.