I’ve been growing a crop of anise hyssop (Agastache foeniculum) in a planter on my roof garden for several years now. It’s hardy enough to survive the extreme heat, wind, drought, and cold on the roof. Unfortunately, it’s also an aggressive self-seeder, which means its progeny pops up in every nook and cranny in the spring, continuing to produce new seedlings throughout the growing season.
I’ve wasted hours of my life so-far weeding out the babies but I’d grow it again despite the hassles. The flowers attract all manner of pollinators and beneficial insects to the roof, the birds like the seeds, and I like the flowers in tea. Sometimes it’s just nice to run my hands over the leaves and flowers for the smell, which is a mix of licorice or anise and mint with a hint of fruitiness.