As the stems mature in future years, they will be able to hold the blooms better. You could add wire supports to the weak stems or surround the plant with a small wire fence that will hold the stems. The best time to add these is during the winter (do it now if it bothers you) since you can see the structure of the plant and the stems clearly. Then as the plant leafs out, the supports tend to disappear, covered by the leaves.

I am wondering how long it takes them to mature. My EM is 6 years old and my BB's are 4. Interestingly my Glowing Embers is only 3 years old and it is doing fine. Could it be that the whites tend to have weaker stems than the pink/blues?

I was never hugely fond of lacecaps and bought my Blue Bird by accident (thinking it was a mophead). Now I am becoming more partial to them. It looks great with its blooms held high!

I too was not fond of lacecaps but like them now. My first lacecap was a mislabeled Nikko Blue. You can imagine my shock when the blooms started to open. They sure "did not look right" and I started wondering what was up with that!?!? LOL!