All parts of hyssop, leaves, flowers, young shoots, can be used. Uses: Relieves congestion and acts as a decongestant allowing you to cough up mucous. It also helps to relieve gas and can control blood pressure. The fresh leaves will promote healing if applied as a poultice to a wound or sore. This plant is easy to grow (I live in zone 6) and is a beautiful garden plant. I grow anise hyssop which has a mild mint/anise flavor. These leaves are good in salad or can be your “secret ingredient” in a soup. Especially good in a fruit salad, too.