@adfbf87b is this bronze fennel, or the bulbing type?  I love to eat the bulbing type and I found it to be kind of perennial.  Cut a bulb, leave the root, and often I'd get a new bulb.

Sadly, I've only had butterflies eating it one year.  I like butterflies. 

 @ec45f895 just green fennel but not bulb fennel. I really like the bulbing type too but I think bugs would chew it up and it would be gross.