While oregano evokes images of scrubby herbs on Mediterranean cliffs, in reality it's a champion of the cold, one of the first perennial herbs to emerge from winter dormancy. It rarely dies back entirely and can often be harvested year round. Essential in a range of cuisines, oregano imparts a distinctive, rich, savory aroma. Seedlings can be slow to grow, but well-established plants will provide for years without asking for much in return.