Addiction is IS! How large did you say that bed was??? LOL
The coneflowers are actually an herb too. Later in spring, you will find pots of Echinacea or coneflowers for sale at the garden centers. They will bloom more quickly than starting from seed. And, the butterflies will love the coneflower blooms.
Have to admit, I'm a Crinum fan also. Three different ones and all were passalong bulbs. My favorite is a summer bloomer that is ever so fragrant with a white bloom.