I received a cutting of the tetraploid "Clear Sky" in a trade two years ago. I planted it in the ground, but despite good growth, it never flowered. Didn't even try to set buds. The only thing it was good for, it seemed, was a caterpillar buffet. I was, understandably, frustrated.

Yesterday I was in the back yard and noticed it'd set a dozen flower buds. Imagine my relief--I'd pretty much decided if it didn't flower this summer I was going to pull it up and go with something else. Yay!