Hyssop is an herb of great antiquity. It has a wise, benevolent energy, fresh fragrance, and it propagates readily. The usual planetary attribution for Hyssop is Jupiter.
This works out very well, because Hyssop is specifically linked to the sky-god Jehovah. (Agrippa attributes Hyssop to the Moon.)
The main magical property of hyssop centers around cleansing, protection and purification. It can be used either as a dried herb or as an oil. Highly versatile and potent it’s origins stretch back far into the history of witchcraft and still has a lot of modern-day usage.