Lettuce and lettuce are the same, lettuce, also known as lettuce, annual or biennial herbs. It is 25-100 centimeters tall, with erect, solitary stems, basal and lower stem leaves large, undivided, oblanceolate, elliptic, or elliptic-oblanceolate, acute, shortly acuminate, or rounded at the tip, sessile, and the leaves on the lower part of panicle branches and on the upper part of panicle branches very small, ovate-cordate, and sessile.

Heads numerous or very numerous, arranged in panicles at the tips of stem branches. Achenes oblanceolate, compressed, light brown, apically acute into a fine beak, the beak finely filiform, several times as long as the achenes, flowering and fruiting February-September.

Expanded Information

Growth habit: Lettuce is a cold-hardy vegetable, preferring cooler climates and not tolerating high temperatures. The germination temperature is above 4℃, 15-20℃ is the best, if the temperature is more than 30℃, it will not germinate. Seedlings can tolerate sub-zero temperatures, the appropriate temperature for seedling growth is 15-20 ℃, the growth temperature of the stem is 11-18 ℃. Lettuce like day and night temperature difference, flowering and fruiting require higher temperatures, the appropriate temperature for 19-22 ℃.

Response to the soil surface moisture state is extremely sensitive, need to constantly supply water to keep the soil moist. And the need for fertilizer is large, suitable for growth in organic matter rich, water retention and fertilizer clay loam or loamy soil. Lettuce like slightly acidic soil, suitable for soil pH value of 6.0 or so.