Leaf Lettuce
Ruby Sky Lettuce is Johnny's Selected Seeds' most productive red leaf variety, a cool-season green that reaches full maturity in just 58 days from transplant. This open-pollinated cultivar thrives in the crisp conditions lettuce loves, ideally 60, 65°F, and delivers reliable harvests whether you're growing full heads or cutting for continuous salad mix. With robust resistance to Downy Mildew and Lettuce Mosaic Virus, it's built to handle the diseases that typically plague leaf lettuce in spring and fall gardens.
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3-9
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Annual, Biennial
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What sets Ruby Sky apart is its consistent productivity as a red leaf variety, coupled with genuine disease resistance that keeps plants healthier longer. The 58-day timeline from transplant means you can succession-plant every two to three weeks and enjoy overlapping harvests throughout the cool season. Its open-pollinated genetics mean you can save seed from your best plants, reconnecting you to the rhythm of seed-saving gardening. The variety germinates reliably below 70°F, making it far more dependable than heat-lovers in spring and fall planting windows.
Ruby Sky is grown for fresh salad harvests, whether you're picking individual outer leaves for continuous cutting or allowing plants to form full heads for a single harvest. The red leaf coloring makes it attractive in mixed green salads and as a visual component in composed dishes where color matters. Its productivity as a salad mix ingredient means many gardeners use it in the quick-harvest, frequent-cutting method rather than waiting for full head formation.
Start Ruby Sky indoors 4–6 weeks before your target transplant date, keeping seed trays cool—below 70°F for best germination. Sow seeds shallowly about 1/8 inch deep in moist seed-starting mix and maintain cool conditions; seedlings are ready to transplant when they develop their first true leaves, typically within 7–10 days of germination.
Transplant hardened-off seedlings into the garden as soon as soil can be worked in spring, or 6–8 weeks before your first fall frost. Space plants 6–12 inches apart depending on your harvest method—closer spacing if you're harvesting individual leaves frequently, wider spacing if growing full heads. Soil temperature should be at least 40–45°F, though 60–65°F is ideal for vigorous growth.
Direct sow Ruby Sky seeds outdoors in cool-season windows by pressing seeds shallowly into moist soil and keeping the seedbed consistently moist until germination, which occurs within 7–10 days below 70°F. Thin seedlings to 6–12 inches apart once they've developed their first true leaves.
Ruby Sky reaches harvest maturity in 58 days from transplant. Begin harvesting outer leaves once the plant is established and about 4, 6 inches tall, pinching off the oldest outer leaves to encourage continued production, this method keeps plants yielding for weeks. Alternatively, allow plants to form fuller heads and harvest the entire plant by cutting at soil level; head-type harvests are best done in the cool morning when leaves are crisp and full of moisture. For salad mix cutting, harvest when plants are 4, 6 inches tall and tender, using scissors to cut just above the soil line.
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