Scent in plants is due to potent essential oils contained in minute glands on or within one or more parts of a plant. The petals, stamens and pollen of most flowers contain these essential oils, providing us with some of the most exquisite of fragrances. In some plants however, these oils may flourish in the foliage of a plant as with mint and thyme. A number of oils are also found in bark as in cinnamon or in wood as in sandalwood and the incense cedar. Plants including the lemon and orange contain essential oils in the rind of the fruit while in others these oils are found in the root or rhizome of a plant as occurs in orris root.
Many plants release their scent freely with their fragrance drifting great distances.
Their detection is sometimes influenced by temperature and other climatic conditions. Often a plant's essential oils are stored on the leaf surface in easily broken flask or globe-shaped cells. These plants should therefore be positioned where their foliage can be touched or brushed against. It is the chemical make-up of essential oils that determine the scent's character. These scents encompass a wide variety of fragrances such as aromatic, sharp, sweet or richly pungent.