I am planning on growing these partially for the flowers to attract beneficial insects and partially for some height interest at the edge of my plot.

Can anyone clarify when to buy and plant them, some sites say they will deliver in November and other sites say plant them in Feb/March.

Does/will anyone have any extras that they are willing to pass on to me? I will, of course, cover any costs involved.

I was also thinking of growing sunflowers in amongst them. Are they compatible? I understand they are of the same family?