Lactuca sativa.
The very symbol of the North American salad of the 20th century. The original Iceberg variety was released in 1894 by the Burpee house, who named it that way to evoke the icy whiteness of its heart. The image was then reinforced in the first half of the 20th century by the Californian railway industry — the tight, heavy heads were shipped toward Eastern cities packed in crushed ice, and the freight cars are said to have resembled ice floes from which these pale heads emerged. For half a century, this was what defined the word "salad" in North American grocery stores.
A round, dense head weighing between 500 g and 1 kg, with pale green outer leaves brightening toward the heart into brilliant cream-white leaves, water-laden, ultra-crunchy and of a deliberately discreet flavour. Long mocked for its blandness — "crunchy water," say its detractors — it has experienced a rehabilitation in contemporary chef cuisine in recent years: its freshness and texture make it the unequalled base of the American wedge salad (a quarter of head drizzled with Roquefort dressing and bacon), the BLT sandwich, the Vietnamese banh mi and fish tacos, where it brings a crunch nothing else can match. Good refrigerator keeper — a whole head lasts one to two weeks.
Grower's tip: Iceberg lettuce is more capricious than its leaf-type cousins. It needs a full cycle of cool-weather growth to head properly — if heat arrives too early, it bolts instead of forming its characteristic head. In Québec, that means an indoor start in March-April for an early transplant, or a late-July summer sowing for the fall harvest (often the most successful). Space generously, 30 cm apart — the heads need room to form fully. And water regularly and deeply: water stress wrecks head formation.
- Open-pollinated. Self-fertile, so very few crossings to fear.
- Height: 25 to 30 cm.
- Maturity: 70 to 85 days for full heads.
- Exposure: full sun; part shade in summer heat.
- Rich, fresh, well-drained soil, kept constantly moist. Thin to 30 cm.
- Indoor start 4 to 6 weeks before planting out for summer harvest, or direct-sow late July for fall harvest. A single window per season — the heat of July-August prevents head formation.
