Sheesh, that is insanely huge. I have this cultivar and have to say, it thrives with the most grim sandy soil, no water ever and blazing sun (I suspect the all day sun is the key issue although English sun is laughably meek compared to say, Texan sun.). I have a palin B.australis which gets less sun because a bloody great spindle tree hovers over it.....although it just looks feeble (and largely flowerless) without any of that lush growth yours gets - do you feed it?

Typically lush growth and few flowers means too much nitrogen. Have you tested your soil?

I have not fed it other than the lobster-compost I bought in bags when I prepared this garden in 2006. I planted this Baptisia in 2007, and moved it in 2010. I have added only free (fresh) wood chips from our town DPW as a mulch, and they are supposed to ROB a garden of nitrogen.

simcam, I have never had my soil tested, but this may be a good time to start!

Not meaning to rub your nose in it luckyladyslipper but all of my Baptisias bloomed heavily this year. My soil is slightly acidic sandy loam. All mine are growing in full sun.

According to one of my books, Perennials For Every Purpose by Larry Hodgson:

'...these plants even supply their own fertilizer. They're legumes so they develop their own colonies of nitrogen-fixing bacteria on their roots.'

Check out the site below for additional information.

Here is a link that might be useful: Missouri Botanical Garden

Well, this guy has fixed his nitrogen, for sure! I could do with less bush, and more flower. I had checked Missouri Botanical Garden, too. They actually have an entry for 'Purple Smoke' - but it sheds no light on my problems. I guess I'll go with my gut and scratch in some superphosphate.

They highly resent moving, but it should have recovered by now from 2010. I have noticed the same clumps don't necessarily flower heavily each year in the wild in Oklahoma, but I think you likely have an environmental condition, so try superphosphate and see for next year.
Good luck!

Many years ago I read somewhere that they like acidic soil, so I added aluminum sulfate in the fall, which increased significantly the number of flowers I had. This past fall I forgot to add it, and this spring I again had very few flowers.

I can't have this wonderful plant because I do not have enough sun and my soil is to fertile. I have heard it likes lean soil>>no amendments and no fertilizer.

Thanks, Digging, I may try aluminum sulfate, then.

Shadey, this guy has had no amendments since before I planted him in 2007, and he has bloomed rather well in previous years, though I can't seem to find a photo. The first few years it was beautiful at the same time my poppies were profuse - which actually is why I moved it from the left side of the window behind the peonies you can't see, to the right side. Then the poppies were eaten one devastating winter. Alas, the life of a garden!