I got busy, it started blooming, it looked pretty, the bees loved it, the passers-by asked about it and the next thing I knew I hadn't ripped out the Jupiter's beard. Anyone know of a centranthus birth control? Contraceptive bees, perhaps?
A nice substitute in a part-shade area of the garden is a carmine-colored spirea and it is more dignified and well-behaved. However, it doesn't carry the same stately garden drama as centranthus.
Yesterday I planted a nice buckwheat, and today I'm putting in mirabilis multiflora and a taller perennial linaria. These are all experiments.
I've got the summer to sit back and let things figure themselves out.