Concept Lettuce
A dark green heat-tolerant romaine/summer crisp cross with tender leaves and great flavor. Good for year-round production in Hawaii. Optimum growth occurs on well drained, fertile, high organic matter soils with a pH of 6 - 7. Irrigate frequently to provide continuous moisture and to cool the soil but avoid water logging. Seeds do not germinate at temperatures above 90°F. Lettuce is one of the richest vegetable sources of choline (an essential brain nutrient).
Lettuce can be direct seeded or transplanted. Plant lettuce every 3-4 weeks for continuous harvests. Sow less frequently during cool spring and fall conditions. Optimum germination occurs at soil temperatures from 60–70°F. Plant 2 seeds per cell, 1/8th inch deep. Thin to 1 plant per cell. Harden-off seedlings for 5–7 days prior to transplanting. Transplant 3-4 week old seedlings outside in a fertile garden bed, 12 inches apart, allowing 18–24 inches between rows. To direct seed, plant seed 1/8-1/4 inch deep, 6 seeds per row foot, allowing 18–24 inches between rows.
Having plants dry when the sun goes down can minimize diseases such as Downy and Powdery Mildew, and butt rot. Good ventilation and air flow is important to mitigate diseases. Do not crowd plants. Disease pressure for this and other lettuce diseases may be mitigated by increasing row spacing, orienting rows for optimum air flow, using drip irrigation, and practicing crop rotations. Provide adequate Calcium and avoid excessive Nitrogen and Phosphorus to prevent tipburn. Even watering will also help to minimize this physiological problem.
Cut lettuce heads at the base when they reach full size. If let to stand in the garden too long they will start to elongate and go to seed, which turns them bitter. Wash in cold water and store in the refrigerator to crisp up. Tender oakleaf and butterhead varieties are fragile and should be handled as little as possible. Loose leaf types can be harvested gradually by pulling off a few outer leaves at a time, leaving the central heart to continue growing to maturity. This practice will result in smaller finished heads.
50 seeds per packet
Seeds grown on Molokai.