Marrubium vulgare (white horehound or common horehound) is a flowering plant in the mint family (Lamiaceae), native to Europe, northern Africa, and southwestern and central Asia. It is also widely naturalized in many places, including most of North and South America.
It is a grey-leaved herbaceous perennial plant and grows to 25–45 centimeters (10–18 in) tall. The leaves are 2–5 cm (0.8–2.0 in) long with a densely crinkled surface and are covered in downy hairs. The flowers are white, borne in clusters on the upper part of the main stem.
Horehound drops are bittersweet hard candies made with sugar and an extract of M.vulgare. They are dark-colored, dissolve in the mouth, and have a flavor that has been compared to menthol and root beer. Like other products derived from M.vulgare, they are sometimes used as an unproven folk treatment for coughs and other ailments.
I do not have an indoor garden so I am waiting until spring to plant. I will try planting closer to Feb or March in small pods watering with spray bottle, and slowly introduce the plants to outdoor conditions.