Great Lakes
70d to harvest
Crisp as fresh-cut glass, Great Lakes lettuce forms a dense, uniform head with a cool, sweet snap and a clean, refreshing bite. The leaves are thick and sturdy—deep green to blue-green on the outside, pale and buttery within—holding their crunch beautifully in the garden and on the table. Ideal for crisp salads and elegant platters, Great Lakes is a crisphead favorite for gardeners who want dependable, head-forming performance at about 70 days.
Crop Dates
| Milestone | Date |
|---|---|
| Start Indoors | Mar 11th |
| Last Frost | Apr 1st |
| Transplant / Sow Outdoors | Apr 1st |
| Harvest Begins | Jun 10th |
| Harvest Ends | Nov 5th |
Crop Details
| Trait | Value |
|---|---|
| Days to Maturity | 70 |
| Sun Requirements | Full Sun |
| Growth Habit | Rosette |
| Support Needed | None |
| Planting Depth | Surface |
| Germination Temp (°F) | 45 |
| Min Soil Temp (°F) | 40 |
| Min Night Temp (°F) | 32 |
| Harden Off (days) | 6 |
Recommended Companions
Frequently Asked Questions
What pest or disease is most likely on Lactuca sativa (iceberg-type lettuce) and how do I treat it?
Iceberg lettuce (Lactuca sativa) is especially prone to downy mildew (often seen as pale yellow patches on leaf tops with fuzzy gray-purple growth underneath). Improve airflow by spacing plants and water the soil (not the leaves), then remove badly infected leaves immediately to slow spread. If it keeps recurring, treat early with a labeled fungicide for downy mildew on edible greens, following the product’s waiting period before harvest.
How can I tell when Great Lakes (Lactuca sativa) is ready to harvest?
Harvest when heads feel firm and reach about full size for your planting spacing; at 70 days from sowing or transplanting, timing typically lines up with head firmness. The outer leaves should be crisp and green, with no significant bolting (flowering stalk) starting in the center. Cut the head at the base with a sharp knife in the morning for best texture.