All cultivated varieties of lettuce belong to one botanical species – Lactuca sativa (the most widespread is the cultivation of butter lettuce). The biological value of lettuce is mainly due to the fact that it contains a good amount of mineral salts: calcium and iron and vitamin A., B,, B2, E i C. Lettuces are classified into: butterheaded, fragile headed, Roman, leaf or rosette, stalk (asparagus).
Headed buttery lettuce. Lettuce is a cool climate plant. It grows best and sets heads at temperature 12-1 5°C. In hot weather, butter lettuce ties small heads, loose, with hard and bitter leaves, and in hot and humid weather it rots easily, although it requires large amounts of water. Well-hardened young plants can withstand frosts down to -6 ° C, which allows very early sowing or planting into the ground. In the conditions of a long day, butter lettuce quickly breaks into flower shoots. Lettuce grows best in humus soil, fertile. For early butter lettuce, sandy loam soil is more suitable, heavier or peaty soils are good for later varieties, better water retention. The pH of the soil should be close to neutral.
The lettuce is grown as a forecrop, coordinates (Total) with other vegetables (slow rising and slow rising) or as an aftercrop. As a forecrop, lettuce is grown in the first year after manure. It grows best in a place covered with compost or well-distributed manure (4 kg/m2), given very early in the spring. Weaker soils are additionally fertilized in the following proportions: 10 g of calcium ammonium nitrate, 20-30 g superfosfatu i 20-30 g of potassium salt per 1 m2. You can also use one of the multi-component garden fertilizers, e.g. Azophos (50-90 g na 1 m2). During the growing season, we feed the lettuce with ammonium nitrate (10 g na 1 m2).
Lettuce is grown from sowing or seedling, the earlier and the larger heads are obtained from seedlings. Lettuce is sown into the ground as early as possible in spring rows 20-30 cm, placing the seeds in depth 1 cm. To sow 1 m2 required 0,2 g nasion. Seeds for seedlings are sown in early March in apartment boxes or on a cold inspection (temperature 12-15 ° C), in an amount 1 g / m2 in rows every 5 cm. At the beginning of April, the seedlings are planted into the ground with a spacing of 30-35X20-25 cm. To have a continuous crop, butter lettuce seeds co 2 weeks until mid-April. From late May to mid-July, they are sown again for autumn use.
Nurturing consists of weeding and watering as needed. Also, as already noted, top dressing with nitrogen fertilizers.
The heads are collected gradually as they curl up.
The earliest type of butter lettuce is Rakowicka. The period from sunrise to formation of the head is 60-75 days. The heads are spherical, hard, well developed by weight 150-180 g. Yellowish-green leaves, delicate and brittle, very good taste. It quickly kills the seed.
The Queen of May is a bit later than her. The period from sunrise to head formation continues 60-80 days. The heads are spherical, slightly flattened at the top, medium hard, well closed, about weight 160-200 g. Yellowish-green leaves, there may be a reddish coating, not very prone to knocking out the seed shoot. Large leaf, hard, firm.
Ace is slightly later than her 44. It is more difficult to knock out seed shoots. The heads are big, almost spherical to slightly elongated, about weight 1 50-250 g, outer leaves light green with a yellow sheen. The consistency of the leaf tissue is delicate, fragile, excellent in taste – no bitterness.
Meisterstuck is a medium-early variety. Good for early field cultivation, creates large heads, spherical in the upper part convex or slightly elongated, weight from 150 do 350 g. The surface of the leaves is wavy in light yellow color. Plenna, very good taste, sweet, delicate leaf, fragile.
The Miracle of Voorburg is medium late. It does not hit seed shoots very quickly. The heads are spherical, sometimes slightly elongated, close, hard, well closed, about weight 200-300 g. Yellowish light green leaves. Pretty sensitive to disease.
Nochowska is also a medium late variety. Creates fairly large heads, spherical and convex in the upper part, medium-hard to hard, very well closed. Yellowish green leaves, sometimes tinted red. Plenna, with a delicate flavor, resistant to long days and high temperatures, and therefore suitable for late spring and summer cultivation.
The late variety is Bautzeńska. Medium large head (250-300 g) spherical, slightly flattened, strict, well closed. Leaves almost smooth, whorls and yellowish-steel-greenish over the head, matte, internal light greenish cream, firm, quite hard. Durable for a long day and high temperatures.
The latest variety is Dippego. Creates large heads, hard, closed, wide spherical. The outer leaves and heads are intensely green with a low gloss. The consistency of the leaf blade is quite hard, leathery, slightly bitter taste.
The winter variety of butter lettuce is Winter Nansena, intended for winter cultivation in regions with milder winters., for early spring harvest after winter in the ground. Spherical head, medium high, strict. Light yellowish green leaves. Brittle leaves, with a delicate flavor. It can also be grown in early spring and for autumn harvesting.