“Lettuce is one of the few crops where the harder you harvest, the more it gives you back.”
Lettuce is the crop that rewards impatience. Leaf varieties are ready in 30 to 45 days from transplant (faster than almost any other vegetable), and the right harvest technique means a single planting keeps giving for weeks. The main challenge is keeping production going through warm weather. Because lettuce is a cool-weather crop that bolts and turns bitter when summer heat sets in, many home gardeners get a short spring flush and then nothing until October. This guide covers variety selection, succession sowing, soil preparation, spacing, pest management, shade strategies, and cut-and-come-again harvesting to maintain salad greens from March through November.
Lettuce fits naturally into the kind of intensive, layered kitchen garden that raised-bed and square-foot growers already use. Its shallow root system occupies the top six inches of soil, which means it coexists happily with deeper-rooted neighbors and tucks into the gaps of a companion-planted bed without competition.
The most important number to know going in: 75°F. Above that threshold, lettuce shifts its energy from leaf production to seed set, known as bolting. Every strategy in this guide is designed to keep lettuce below that line, or to buy extra weeks when the temperature rises anyway.
Key takeaways
Lettuce produces steadily from early spring to late fall with regular harvesting. A ‘cut-and-come-again’ method maintains fresh salad greens for months.
- Lettuce grows best between 55 and 68°F and bolts once temperatures push past 75°F; variety choice and timing are your first defenses.
- Sow a new batch every 10 to 14 days from early spring through midsummer, then again in late summer for a fall crop.
- Cut-and-come-again harvesting (cutting the whole plant two inches above the soil) extends a single sowing by two to three additional cuts.
- Batavian types (Nevada, Sierra, Tahoe) are the most bolt-resistant varieties in university trials; oak-leaf types are the runner-up.
- Containers moved to afternoon shade and 30–50% shade cloth extend summer lettuce production in most North American climates.
- Store harvested lettuce dry at 32–36°F; leaf and bibb types keep up to four weeks when bagged without moisture.
Choosing the right lettuce type and variety
There are five distinct lettuce types, and they are not interchangeable in the garden. Each has a different cold tolerance, bolt resistance, days to maturity, and ideal harvest method. Picking the wrong type for your season is the most common reason a planting fails before pests or weather ever become a factor.
Five lettuce types arranged side by side: loose-leaf, butterhead, romaine, French crisp, and crisphead iceberg varieties in a market display
The five main lettuce types differ significantly in days to maturity, heat tolerance, and harvest method; choosing the right one determines how long your harvest window stays open.
University of Minnesota Extension identifies the five types as loose-leaf, butterhead, French crisp (Batavian), romaine, and crisphead (iceberg). Here is how they line up for a home kitchen garden:
Type | Days to maturity (transplant) | Heat tolerance | Best season | Harvest method |
|---|---|---|---|---|
Loose-leaf | 30–45 days | Low–medium | Spring / fall | Outer leaves or cut-and-come-again |
Butterhead (Bibb) | 45–55 days | Low | Spring / fall | Head or outer leaves |
Batavian / French crisp | 55–65 days | High | Spring through summer | Head or outer leaves |
Romaine (cos) | 55–65 days | Medium | Spring / fall | Head or outer leaves |
Crisphead (iceberg) | 60–70 days | Very low | Cool spring only | Full head |