Ruby Sky

Family: Asteraceae Leafy Green

Planting Schedule

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Ruby Sky unfolds in a lush, loose-leaf rosette where tender leaves blush from cool green to vivid ruby-red at the edges, like dawn light on velvet.

Expect a crisp, juicy bite with a mild, refreshing flavor that stays pleasantly sweet—ideal for gardeners who love greens that look as good as they taste. Grow Ruby Sky for abundant harvests over a long season, perfect for fresh salads, bright wraps, and vibrant garnishes that lend color to every bowl.

Light: Part SunMaturity: 50 DaysHabit: Rosette

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Ruby Sky Planting Dates by USDA Zone

Estimated US hardiness-zone windows for sow, transplant, and harvest. Enter a US ZIP above for exact local dates, or open a zone below.

Zone	Start Indoors	Sow / Transplant	Harvest
Zone 1a	Protected Environment Only
Zone 1b	May 4th	May 25th	Jul 14th – Aug 1st
Zone 2a	Apr 27th	May 18th	Jul 7th – Aug 29th
Zone 2b	Apr 17th	May 8th	Jun 27th – Aug 25th
Zone 3a	Apr 17th	May 8th	Jun 27th – Sep 1st
Zone 3b	Apr 21st	May 12th	Jul 1st – Sep 21st
Zone 4a	Apr 17th	May 8th	Jun 27th – Sep 24th
Zone 4b	Apr 15th	May 6th	Jun 25th – Sep 27th
Zone 5a	Apr 10th	May 1st	Jun 20th – Sep 30th
Zone 5b	Apr 6th	Apr 27th	Jun 16th – Oct 5th
Zone 6a	Apr 3rd	Apr 24th	Jun 13th – Oct 10th
Zone 6b	Mar 28th	Apr 18th	Jun 7th – Oct 16th
Zone 7a	Mar 23rd	Apr 13th	Jun 2nd – Oct 20th
Zone 7b	Mar 13th	Apr 3rd	May 23rd – Oct 28th
Zone 8a	Mar 4th	Mar 25th	May 14th – Nov 5th
Zone 8b	Feb 23rd	Mar 16th	May 5th – Nov 12th
Zone 9a	Feb 6th	Feb 27th	Apr 18th – Nov 26th
Zone 9b	Jan 12th	Feb 2nd	Mar 24th – Dec 9th
Zone 10a	—	Oct 1st	Nov 20th – Feb 28th
Zone 10b	—	Oct 1st	Nov 20th – Feb 28th
Zone 11a	—	Oct 1st	Nov 20th – Feb 28th
Zone 11b	—	Oct 1st	Nov 20th – Feb 28th
Zone 12a	—	Oct 1st	Nov 20th – Feb 28th
Zone 12b	—	Oct 1st	Nov 20th – Feb 28th
Zone 13a	—	Oct 1st	Nov 20th – Feb 28th
Zone 13b	—	Oct 1st	Nov 20th – Feb 28th

Crop Details

Trait	Value
Days to Maturity	50
Sun Requirements	Part Sun
Growth Habit	Rosette
Support Needed	None
Planting Depth	Surface
Germination Temp (°F)	65
Min Soil Temp (°F)	40
Min Night Temp (°F)	32
Harden Off (days)	6

Culinary Notes

Chef's Note

Ruby Sky’s loose-leaf structure makes it stay snappy and watery, not stringy, so it performs best raw—especially under a citrusy, not-too-thick dressing. The ruby edges bring visual pop, making it an easy choice when you want greens that look alive and bite back.

Best Uses

fresh salads where it can hold crunch
color-forward wraps that don’t need heavy dressing
tossed with citrus vinaigrette to keep it bright
garnish for sandwiches and grain bowls

Flavor Profile

crisp, juicy snap mildly sweet finish cool, refreshing green-note

Kitchen Pairings

lemon olive oil goat cheese cherry tomatoes balsamic vinegar

Frequently Asked Questions

What pest or disease most commonly affects Lactuca sativa (lettuce) and how can I manage it?

Lettuce is commonly hit by aphids and mildew, especially when plants stay damp. For aphids, spray plants with a strong jet of water and spot-treat heavily infested heads/leaves; for mildew, improve airflow by thinning to proper spacing and water at soil level instead of overhead.

How often should I water Lactuca sativa during the main growing phase, and what soil moisture level should I aim for?

During the main growth period (roughly weeks 2–6), keep the soil consistently evenly moist—about 1–1.5 inches (2.5–3.8 cm) of water per week in total, adjusted for rainfall and heat. Let the top 1 inch (2.5 cm) dry slightly between waterings, but don’t let the root zone dry out, since lettuce quickly turns bitter when it stresses.

How do I tell when Lactuca sativa is ready to harvest?

Harvest Ruby Sky about 50 days from sowing when heads are fully formed and feel firm to the touch, with leaves that are crisp rather than limp. Cut at the base in the morning for best texture, and if your plants start to stretch upward or flower (bolting), harvest immediately because quality drops fast.