Aconitum, Carmichael's Monkshood, Wolfbane 'Arendsii'

A very valuable plant for extending the season, with a good long display of intensely blue-violet flowers beginning here in late Septembe...Read Morer. No deadheading necessary. One of the best plants for fall bloom in part shade, with Japanese anemonies and Actaea matsumurae (Synonym Cimicifuga simplex). The leaves are handsome, deeply cut and a glossy dark green.

The stems grow stronger and taller and more floriferous the second year. Mine reached 6' in dappled shade. Stems are rigid and vertical, but in shade they needed light support (no staking, just a string across if stems begin to lean).

The roots are radish-like, and don't have a lot of fibrous rootlets. This plant resents transplanting, which is best done in very early spring before there's much top growth---plants emerge from dormancy in earliest spring. I would not space these closer than 12-18".

This plant is less drought tolerant and requires more consistent moisture than most garden perennials, and I find partial shade (or at least protection from hot afternoon sun) helps keep it from drying out in the heat of summer. I suspect this is more important in the southeastern USA (I'm in Boston Z6a). It doesn't prosper where summer nights often remain above 70F. It doesn't seem to mind heavy silty soil, which helps with moisture retention.

In some years it seems to get a disease that blackens the leaves---this seems to follow drought stress, and the disease doesn't necessarily come back the next year.

The juice is highly poisonous---meat laced with it was once used to poison wolves, hence the name "wolfbane"---and the neurotoxins in the juice are easily absorbed through the skin. Use gloves when handling plants! Initial symptoms include numbness and tingling.

Aconitum x cammarum is a hybrid between A. napellus and A. variegatum. It blooms in summer, and commonly has bicolored flowers. It is not a synonym for A. carmichaelii.

I have a blue & purple "themed" flower garden, and saw monkshood at my local nursery in 2011- the fabulous intense blue/violet flowers ha...Read Mored a definite WOW factor. Received conflicting info as to where to plant, so at first located it in an area where it got the morning sun-got very leggy with not much of a flower stalk the first year. Relocated to a full sun spot in Spring of 2012, and what a difference; plants did get quite tall, over 7 ft, but the top 2 ft were nothing but flowers, and bloomed from mid-Sept to mid-Oct. The plant did tolerate the transplant very well. Did it in early Spring when new shoots were about 6"-just made sure it was well watered for the first week

I had gotten these plants in 2008 from someone on Craigslist thinking I was getting Delphinium plants. Of course when they bloomed in fal...Read Morel I figured out it was the wrong plant.
This plant has done very well where it was planted getting nice green leaves and sending up shoots of flowers in the fall over 6ft tall. The flowers are kinda pretty as long as the stalks stay up and they were displayed in groups otherwise kinda eh. With this plant I do recommend staking the flower stalks. The flower bed this plant was growing in really needed to be cleaned up due to the over growth of the Bee Balm, the garden Phlox that have gone wild (and no longer were or represented the original plant) and other issues in this bed. I with careful consideration decided to remove these plants from the flower bed with no relocation being done, they ended up in a trash heap. Several deciding factors played a role in this:
1)The whole plant is extremely toxic to pets and I had obtained 2 small breed puppies and did not want to take any chances since the plant was growing out of its designated fenced in area.
2)The plant just got way to tall for where it was located with the foliage getting3-4 feet and the flower spikes getting to 6ft
3)I wasnt all the impressed with the flowers to make it worth my while
4)The flower stalks needed staking and I am to lazy to do all that for a plant I am not that impressed with.

So I have officially removed this plant this year(2012) and am no longer growing it.

Beautiful blue fall monkshood. Leathery shiny dark green leaves. Thick stems, typically three to four foot in height, usually don't need ...Read Morestaking. Long lived. Very poisonous.