Mirror

Lettuce

70d to harvest

Crisp as a fresh snowfall, ‘Mirror’ forms tight, luminous heads that hold their snap with a satisfying, glassy crunch. The leaves are tender and buttery-smooth, with a clean, refreshing bite that stays crisp even as the weather cools. Ideal for crisphead salads and elegant, chilled platters—grow ‘Mirror’ for a garden-to-table centerpiece that looks as good as it tastes.

Crop Dates

Milestone	Date
Start Indoors	Apr 17th
Last Frost	May 15th
Transplant / Sow Outdoors	May 8th
Harvest Begins	Jul 17th
Harvest Ends	Sep 1st

Crop Details

Trait	Value
Days to Maturity	70
Sun Requirements	Full Sun
Growth Habit	Rosette
Support Needed	None
Planting Depth	Surface
Germination Temp (°F)	70
Min Soil Temp (°F)	40
Min Night Temp (°F)	35
Harden Off (days)	5

Frequently Asked Questions

What disease should I watch for on Lactuca sativa (iceberg-type lettuce), and how can I prevent it?

Watch for downy mildew (often shows as pale yellow patches on leaf tops with gray-purple growth underneath). Avoid wetting leaves, improve airflow by spacing plants, and water at soil level; if you see symptoms, remove affected leaves to slow spread. Use resistant cultivars when possible and don’t plant lettuce in the same bed for at least a season.

How often should I water iceberg lettuce (Lactuca sativa) during its main growth phase?

During the 2–6 weeks of active leaf growth (before heads fully form), keep soil consistently evenly moist—typically about 1 inch (2.5 cm) of water per week, split into 2–3 sessions during warm spells. Don’t let it swing dry-to-soggy; fluctuating moisture can trigger tip burn and bolting. Mulch lightly to reduce evaporation, and check that the top 1–2 inches (2.5–5 cm) of soil stay moist.

How do I tell when Lactuca sativa (iceberg-type) is ready to harvest?

Harvest at about 70 days when heads are firm and feel tight to the touch (not loose like leaf lettuce). Leaves should be crisp and full-sized, with outer leaves starting to hold their shape around the head. If the head begins to elongate or flowers start to form, harvest immediately—quality drops quickly after bolting begins.