What’s the Difference Between an Herb and a Spice?

And where does lemongrass fit in?

Hooray for Alton Brown on Good Eats, who recently answered a question that I think many of us would know the answer to if we ever thought about it hard and long enough: What’s the difference between an herb and a spice?

It’s funny; we can name them. We can put them in one or the other category, but we often do this without considering what the criteria is.

It’s simple.

An herb expresses its essential oils, and thus flavors and aromas, in the leaves, whereas a spice expresses its flavors elsewhere, such as in its seeds, roots, bark, or unripened berries. Ground ginger or turmeric are rhizomes=spice. Cilantro (or in British English, “fresh coriander”) is a leaf. Basil, parsley, bay leaf, mint? Herbs. Cinnamon, vanilla, cayenne, cumin, mustard seed? Spices.

What’s lemongrass? It’s a “grass,” and grass is leaf-like (chives are an herb, afterall), but it’s really more a stalk, which is a bit tough to actually eat; so in use, it’s more like a spice, right? Like a vanilla bean, it can be steeped. Well, Wikipedia refers to lemongrass as a herb in the first paragraph, and someone known as The Veggie Lady (http://www.theveggielady.com/lemongrass.php) named lemongrass the “herb” of the month at one point. So I guess it’s an herb, even though it’s not quite a leaf.