The Savoy cabbage (Brassica sabauda L.), unlike the white cabbage, shows a blistered structure of both the frame and head leaves. It is more tolerant to frost than white cabbage is, but has a lower storage capacity.
The head has light green exterior color, light yellow interior color, excellent eating qualities and a high vitamin C content. Besides, Savoy cabbage contains mustard oils exhibiting biological activity and phytoncid properties, which is particularly valuable for the nutrition of children and elderly people. In nutritive value, Savoy cabbage is much superior to white cabbage. Savoy cabbage is used for cooking delicious first and second courses: stuffed cabbage rolls, schnitzels, solyanka (a sharp-tasting Russian soup of vegetables and meat or fish), beetroot and cabbage soup (borshch), vegetable soups, etc.
Growing tips
The best preceding crops are annual legumes, cucurbits, winter cereals, early potato and tomato, or onion. For Savoy cabbage cultivation, light-soil fields, which are more readily warmed up in spring, are chosen.
Healthy, uniform transplants are a prerequisite for a high yield of good quality heads. They should be 35-50 days old, depending on the growing technique, and have 4-6 well-developed leaves. The planting pattern is 50 x 40-50 cm. The seeding rate is 50-90 seeds per 10 m2 of open ground. Cassette or potted seedlings become established more readily since no root system injuries occur during transplanting and, consequently, there are no diseased plants. Fertilizers are applied at a rate of 700-750 g ammonium nitrate, 350 g superphosphate and 600 g potassium salt per 10 m2 (N 250, P2O5 75 and K2O 250 kg of active substance per hectare). The phosphate-potassium fertilizers are applied with autumn soil cultivation and the nitrogenous ones as supplementary fertilizing.
Systematic irrigation is a decisive factor in the cultivation cycle. No less than 8-12 irrigations should be given to Savoy cabbage. The irrigation rate is 350-400 l per 10 m2 (350-400 m3/ha) per irrigation prior to heading and 400-450 l per 10 m2 (400-450 m3/ha) after the head formation.
During the growing season, numerous pests such as blue fleas, cabbage aphid, cabbage butterfly and cutworm, cabbage moth, and thrips attack cabbage. Therefore, chemical control is an essential component of Savoy cabbage production technology.
Control measures: on discovering the first signs of infestation, sprays with insecticides such as Sumi-alpha, Zolone, Sherpa, Karate, Actellic, Volaton, etc. should be made systematically in cycles of 7-10 days. Considering the fact that the cabbage leaf has a thick wax coating, it is good practice to admix adhesives (OP-7, skimmed milk or household soap in amounts of 30-50 g per 10 l of water) into the spray solution.
The cabbage root fly, which is the most harmful insect pest attacking cabbage plants, deserves special mention. It starts to fly in mid- or late April when the soil has warmed up to 12-13˚C. The fly lays eggs on the root neck or in the soil around it. The hatching larvae penetrate the roots and gnaw passages in them. As a result, the plants begin to wilt (especially in dry, hot weather), the leaves turn leaden-blue, the growth is retarded or completely terminated and, not infrequently, the plants die.
Control measures: good cultural practices, preventive sprays (at the beginning of flight of butterflies) with the above-mentioned insecticides. Where the plants are attacked by larvae of the cabbage root fly, soil application of 0,15-0,2% Bi-58 or Basudin at a rate of 0,25-0,3 l per plant is recommended. A particularly effective control measure is preplant furrow application of pelleted phosphamide or pelleted superphosphate treated with phosphamide (Bi-58) and hilling-up of plants. Hilling-up prevents the larvae from reaching the plant and promotes adventitious root formation.
Among the diseases attacking brassicas, the most harmful are Black rot, Soft rot and Fusarium wilt.
Control measures: use of tolerant varieties, seed treatment, strict adherence to the crop sequence and good cultural practices.