Description
CULTURE: Lettuce is a hardy, cool-weather crop & can be planted with your earliest worked soil. It grows best at 60-65oF (16-18oC) & germinates best below 70oF (21oC), so careful variety selection is key for success in hotter weather. Sow every 2-3 weeks for a continuous supply of either full heads or salad mix. THERMAL DORMANCY: Lettuce seed can enter thermal dormancy when exposed to high temperatures. Optimum germination results at soil temperatures of 60-68oF (16-20oC). The priming process in pelleted lettuce seeds broadens the temperature range in which the seeds will germinate, overcoming some of their thermal dormancy. TRANSPLANTING for HEAD LETTUCE: 3-4 weeks before field planting, sow in 128-cell trays barely covered with vermiculite or fine soil. If necessary, utilize shade & frequent misting to keep trays cooled below 75oF (25oC) during germination. Young plants properly hardened at least 3-5 days before planting can survive temperatures as low as 20oF (-6oC). Transplant iceberg, romaine, & butterhead lettuce 10-12" apart in rows 15-18" apart, other types 8-10" apart in rows 12-18", & mini heads as close as 6" in a grid. DIRECT SEEDING for BABY LEAF: Seeds can germinate well in soils as low as 40oF (4oC) but often poorly above 75oF (24oC). Sow 4-6 seeds/inch in rows at least 2" apart. Cover lightly to 1/8" & firm gently. Dry soil must be watered to ensure coolness, moisture, & uniform germination. Lettuce Bibb Cegolaine Vegetable Seed 250
