Lactuca sativa.
One of the oldest domesticated lettuce lines — romaine, called "cos" in English after the Greek island of Kos from which it is said to originate, was already cultivated in the gardens of pharaonic Egypt, where it was credited with aphrodisiac virtues. The modern Parris Island selection, more prosaically, was developed in 1952 by the United States Department of Agriculture in collaboration with Clemson University, in South Carolina, and named after the neighbouring island. Goal of the program: a romaine resistant to mosaic virus and tip burn, capable of producing in the stubborn heat of the American South.
Elongated upright head 25 to 30 cm, with crunchy, ribbed medium-green outer leaves and a compact heart of pale yellow-green, sweet, tender, almost buttery. Romaine is the lettuce that best withstands light cooking — grilled cut in half on the barbecue with a drizzle of olive oil, it's a revelation — and the uncontested darling of Caesar salad, itself invented in 1924 by an Italian-Mexican restaurateur of Tijuana. Its hand-held structure and crunchy central rib also make it a perfect vehicle for wraps, lettuce tacos, or simply a sandwich that doesn't go soggy.
Grower's tip: Parris Island was specifically selected for heat resistance, which makes it one of the rare lettuces you can reasonably sow in June for a harvest in the heart of the Québec summer — where the others bolt. For truly firm, well-formed heads, space generously (25-30 cm) and keep the soil constantly moist — water stress leaves a residual bitterness in the heart. Harvest the whole head with a knife while it's still firm, or pick leaf by leaf starting from the outside to stretch the harvest over several weeks.
- Open-pollinated. Self-fertile, so very few crossings to fear.
- Height: 25 to 30 cm.
- Maturity: 65 to 75 days.
- Exposure: full sun; part shade accepted in summer heat.
- Rich, fresh, well-drained soil, kept constantly moist. Thin to 25-30 cm.
- Direct-sow as soon as the soil can be worked (mid-April in Québec), in successive sowings through mid-June, then a new window from mid-August for a fall harvest. Tolerates summer heat better than most lettuces.
