The difference between a Herb and a Spice.
While the terms herb and spice are used interchangeably by cooks and in cookbooks, there are distinct differences between the two.
It all depends on what part of the plant is used. Herbs and spices are obtained from plants. (Salt is neither a spice nor an herb. It is actually a mineral.) Herbs and spices are used primarily for adding flavor and aroma to food. And both are best used fresh but can be saved by drying. While there are similarities, there also are subtle differences between herbs and spices.
Herbs are more fragrant when fresh, whereas spices often are stronger as dried powders.
In general, herbs are the leafy portions of a plant, whether dried or fresh. Examples include basil, bay leaves, parsley, cilantro, rosemary and thyme. They are used for savory purposes in cooking and some have medicinal value. Herbs often are used in larger amounts than spices. Herbs originated from temperate climates such as Italy, France, and England. Herb also is a word used to define any herbaceous plant that dies down at the end of the growing season and may not refer to its culinary value at all.
Spices, on the other hand, are harvested from any other portion of the plant and are typically dried. Popular spices come from berries (peppercorns), roots (ginger), seeds (nutmeg), flower buds (cloves) or even the stamen of flowers (saffron).
Spices are obtained from roots, flowers, fruits, seeds or bark. Spices are native to warm tropical climates and can be woody or herbaceous plants. Spices often are more potent and stronger flavored than herbs; as a result they typically are used in smaller amounts. Some spices are used not only to add taste, but also as a preservative.
Two in One!
Some plants are generous enough to yield both an herb and a spice. Cilantro is the leafy herb of the same plant that gives us the popular spice coriander seed. And dill weed (an herb) and dill seed (a spice) also come from the same plant.