Oooooolalala! Remember Snape in Harry Potter asking Harry if he knew another name for Wolfsbane? Hermione had her hand up madly and poor Harry knew nothing about plants? I was shouting "Aconitum, Aconitum!!!". Ah yes, raising boys....
So this glorious flower is completely poisonous - all parts. Although a powerful medicine, it has been a beloved garden flower since gardens were created and it is a great flower to add to a moist, shady place. I wear gloves when handling the plants and seeds and children should be taught to beware as it can cause skin irritation. Of course do not ingest any part of the plant.
I find it deep in the forest along the creek - almost growing out of the creek. We are usually eye to eye as it can grow 3-6'. It is very impressive in flower as you can see - plants tell us who they are. The leaves are similar to Delphinium.
Like Delphinium, the elk eat it to get high and I am often late to collect the few seedpods they leave me. Gorgeous. It can grow in the garden bed with ample water. It can throw the deepest blue/purple flowers to white and lavender/bi-color in between.
Although it is not necessary, you can cold-stratify for a couple of months, plant in fall or just try it as soon as you receive the fresh seeds - it wants to grow.