Mine bloom in mid-late July (solid blue) and late July to August (blue/white bicolor). They're all in full sun.

Oh gosh, I think some of mine started before the roses started. I have a few different kinds and they are all done blooming now. They have been for a while.

Huh, that is so weird. Mine's solid blue and is just budding out for the first time right now. Luckily it stands up to frost very well. Last October it bloomed with snow all over it.

Gil, you most likely have A. henryi (Autumn Monkshood),
or A. fischeri syn. A. carmichaelii that bloom in the fall.
Aconitum x cammarum `Bicolor' blooms around the end of August and is still blooming right now, I have this one in the shade bed.

Aconitum napellus blooms around mid July, this one is in full sun.

Sharon

Ah that makes sense, thanks Sharon. From what I remember it did look like the solid purple A. henryi that I found on Google. Mystery solved.

Gil, I have the same monkshood. It blooms in Sept/Oct. When I bought mine years ago it was supposed to be a bi-colour, but turned out to be solid purple and a late bloomer.

Sierra

I have that same fall blooming monkshood; love it cause it blooms that beautiful blue after everything else is done. I'm always worried that the frost will get to it before it has a chance to bloom but even with a snow cover it seems to do well. I find the other summerblooming monkshood to be so floppy but arendsi is a sturdy performer and looks good all summer. BTW, I always have read that monkshood don't move well but I moved her wuthout any problem a few years back.

Thanks for posting this. I'm looking for more fall bloomers. I'll have to watch for this one. I seem to have good luck with aconitums.

Well I'd offer to save you some seeds but I don't know if it will ever set seed, blooming so late.

I agree Debbie, it is a very sturdy monkshood and not floppy like some of them.

Oh, rats. Arendsii is actually Aconitum carmichaelii 'Arendsii'. Are there any sturdy monkshood cultivars that bloom earlier in the year?

Thanks,
Sharon