Hyssop is a mint family perennial herb. It has long-blooming purple flowers that the pollinators just love. It grows in a clump, gets about 2 feet tall, and is used in cooking, brewing, and herbal medicine.
These are 3rd year root crowns with a bit of stem attached, bare root.
Photo credit: Sten, CC BY-SA 3.0 <https://creativecommons.org/licenses/by-sa/3.0>, via Wikimedia Commons