Lettuce

Lettuce is the world's most popular salad plant. It's grown worldwide, in over 300 different varieties.

Most of these varieties are fairly mild in taste. For that reason, most people don't eat lettuce just on its own, as you might a radish or a carrot. Instead, we usually eat lettuce in combination with other things with stronger tastes, as in salads and sandwiches. Lettuce's contribution to our taste experience is to provide a cool, crunchy contrast to those other stronger tastes.

"Lettuce" comes from milk

Lettuce gets its name from a Latin word for milk. Thousands of years ago people valued lettuce as much for its thick milky juice as they did for its leaves. Taken from the right varieties and in the right quantity, lettuce juice could make you sleepy and help you get a good night's rest.

It's harvested young

Lettuce is a biennial. That is, it takes two years for lettuce to move completely through its full lifecycle, from taking root, to growing leaves, to flowering and producing seed. If you let a lettuce plant progress through that full cycle, however, you would end up with something that looks like a very big dandelion and doesn't taste too good.

But most gardeners do not let the plant get that far. We harvest it, instead, while it's very young. We often start harvesting lettuce leaves — sometimes full plants — as early as 4 or 5 weeks after the seed has been planted.