Produce

Lettuce

Different lettuce varieties hold up differently in storage and cooking — a sturdier variety like romaine tolerates more handling and even light grilling, while a delicate variety like butter lettuce bruises easily and is best kept for a light salad.

Iceberg lettuce, often dismissed as nutritionally lightweight compared to darker leafy greens, is prized specifically for its exceptional crunch and long shelf life relative to more delicate lettuce varieties.

Lettuce is highly sensitive to ethylene gas released by nearby ripening fruit, which is why storing it away from apples, bananas, or other high-ethylene produce genuinely helps it stay fresh longer.

Iceberg lettuce takes its name from the way growers in California's Salinas Valley once shipped it packed in crushed ice inside rail cars during the early 20th century, a practical shipping solution for a highly perishable crop that ended up giving the variety its lasting nickname rather than any resemblance to an actual iceberg.

Caesar salad wasn't invented in Rome or anywhere in Italy at all — restaurateur Caesar Cardini created it in 1924 at his restaurant in Tijuana, Mexico, reportedly improvising the dish from limited ingredients on hand during a busy Fourth of July weekend rush, and the recipe's core (romaine, egg, Parmesan, garlic, anchovy) has stayed close to that original ever since.

Roughly 95% of lettuce's weight is water, one reason it wilts and loses crispness so quickly once cut or bruised, and why it contributes very little in the way of calories or dense nutrition compared to a denser leafy green like spinach or kale.

Romaine lettuce has been at the center of several major US foodborne illness outbreaks over the past decade, most tied to E. coli contamination traced back to irrigation water or growing conditions in specific regions, prompting the FDA and growers to tighten traceability and water-testing standards across the romaine supply chain.

Butterhead lettuce, including the Boston and Bibb varieties, gets its name from its soft, loosely folded leaves and buttery texture, a genuinely different eating experience from iceberg's dense crunch or romaine's sturdier, more upright leaf, and it's generally considered more delicate and shorter-lived once harvested than either of those two.

Ancient Egyptians associated lettuce with the fertility god Min, depicting tall, upright lettuce varieties (closer in shape to a modern romaine than a round iceberg head) in temple carvings, an association some historians tie to the plant's milky sap, which was linked symbolically to fertility in ancient belief systems.

Indoor hydroponic and vertical lettuce farming has expanded considerably in and around US cities in recent years, letting growers produce lettuce year-round in a controlled environment close to major markets, reducing the shipping distance and time that a more perishable, high-water-content crop like lettuce is especially vulnerable to.

Lettuce's genus name, Lactuca, comes from the Latin word for milk, a direct reference to the milky white sap the plant releases when its stem is cut, the same sap ancient Egyptians associated symbolically with fertility.