Last year, I planted agastache “Black Adder” in my perennial border, and this summer, it has come into its own. Despite its somewhat sinister name, in my opinion, this plant, also known as “giant hyssop,” is a vast improvement over the much more common “Blue Fortune.” The plant seems to be more robust (this one is well over five feet tall but not floppy) and the flowers are a prettier, less dusty blue.
As for bloom period, this plant has been flowering non-stop since June. The pollinators seem to prefer it to all my other plants – even Eupatorium (Joe Pye weed). The flower buds are nearly black – hence the name, I guess – and the flowers are large, up to eight inches tall. I have cut a few for bouquets and they last well, adding vertical interest to my arrangements.
Black Adder is a carefree plant, and grows happily in zones 6 to 9. It prefers full sun, but will tolerate some shade. One condition it will not tolerate is poorly draining soil.
To make it even more appealing, it has that lovely hyssop scent AND it’s deer tolerant. All in all, it’s a very fine addition to the hyssop family.
Digging RI 
Ahhh, a plant that has it all. I love it. I need it. I’m glad you’re enjoying it.
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Maybe you should just get one of your own, Lee!
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I really like agastache plants. I have a couple growing in my garden and they are butterfly and bee magnets. I haven’t noticed this one at the garden centers, but we are zone 5b here, so perhaps that’s the reason. Sometimes zone 6 plants survive our winters, but you take a chance when you plant them.
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It’s probably a zone thing. But I’ll bet you can grow this cultivar, which is called “Little Joe.” I don’t believe your winters are much colder than ours.
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Oops! I was writing about the Joe Pye weed and you were commenting on the hyssop. Sorry, Martha. Anyway, I still think you should give it a go.
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No active blog link attached to the comment you left on mine.
It goes to a dead WordPress blog.
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Argh!!!!!!
Sent from my iPod
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never mind, I’ve added an active link in my reply to yours
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Thanks, Diana
Sent from my iPod
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Joe Pie Weed? I didn’t know they grew in your part of the woods, too, dn. I can just imagine all the little creatures that love your plant. What a joy it is to see them feasting. 🙂
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They most certainly do, CJ. They’re in bloom now along our roadways. The one I grow in my garden is the “Little Joe” cultivar, but it’s still pretty darned tall.
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So delicate, so lovely. Thank you for sharing your garden. Those of us with thumbs less green do appreciate watching the seasons progress through your photos and comments.
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Thanks for your kind words, Leslie, and for visiting my blog.
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stunning new find for me, thanks to generous you!
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So glad you tried this plant. Mine is still going strong so late in the season. Talk about bang for your buck!
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