Cabbages (Brassica oleracea var. capitata) is one of the oldest vegetables grown in the world. The crop require cool moist weather for producing best quality heads, and therefore its cultivation in the state is limited by climate and is restricted to the cooler tracts in the high ranges of Idukki and Wayanad.
Cabbage grows well on a wide range of soils from light sand to heavier clays, but well-drained sandy loam to clay loam soils are ideal for its best growth. The optimum soil pH should be in the range 6.0–6.5. Good drainage is important, and soils that become waterlogged after heavy rain or irrigation are unsuitable.
Propagation & Planting
September, Pusa Drum Head, Golden Acre, Kaveri, Ganga, Sri Ganesh and Pride of India.
The ideal time for planting cabbage is from August-November. Recommended seed rate is 500-750 g/ha. Seeds are sown in nursery beds and three to five weeks old (with 5-6 leaves) healthy seedlings transplanted to the main field. Prepare the field by three or four ploughing and the seedlings are transplanted on ridges at a spacing of 45 x 45 cm preferably in the morning or late evening. Before transplanting, the roots of the seedlings are dipped in a solution of bavistin @ 2g/litre. Clipping two third of the leaves helps to reduce evapo-transpiration losses.
Apply 25 t/ha FYM or compost. Fertilizer dose is N:P2O5:K2O 150:100:125 kg/ha. Apply full dose of P2O5 and half dose of N and K2O before transplanting. Apply remaining half dose one month after transplanting.
Irrigate immediately after transplanting of seedlings and subsequent irrigations are given at an interval of 10-15 days depending upon the season and soil conditions. Avoid water stress from formation to maturity of the head. Avoid excess irrigation at crop maturity to prevent splitting of heads.
Two to three hand weedings and 1-2 very shallow hoeing should be done to remove weeds and to make the soil better aerated. Application of pre-emergence weedicide followed by a hand weeding 60 days after transplanting is also effective in checking the weed population.
Earthing up plants one month after transplanting ensures good size of heads. At the time of earthing up, support the plants with soil to avoid toppling of the plant during head formation.
Diamondback moth (Plutella xylostella)
The caterpillars feed on the leaf epidermis and later make holes in the leaves. Severely affected leaves are completely skeletonised.
Control: Spraying malathion (0.1%) and trap cropping with mustard controls the pest.
Leaf webber (Crocidolomia binotalis)
Caterpillars web up the leaves and live inside the knotted mass affecting flowering and pod formation adversely.
Control: Removal and destruction of webbed bunches of leaf and dusting the crop with carbaryl (4%) or spraying with malathion (0.05%) is effective.
Cabbage borer (Hellula undalis)
The caterpillars mine the foliage, feed on the shoots and finally bore into the stem; and the infested plants get killed or produce side shoots, which do not form heads.
Control: Spraying the crop with malathion (0.1%) or dusting 4% carbaryl gives good control of the larvae.
Cabbage butterfly (Pieris brassicae)
The larvae feed gregariously on the foliage and burrow into the heads, making it unfit for marketing.
Control: The caterpillars should be hand picked and destroyed. Spraying malathion (0.1%) or carbaryl (0.15%) gives excellent control of the pest.
Aphids (Brevicoryne brassicae, Myzus persicae, Lipaphis erysimi)
Nymphs and adults suck cell sap devitalizing the plants and the affected parts become discoloured and malformed.
Control: Spraying of malathion (0.1%).
The insecticide application should be stopped 15-20 days before harvest.
Stalk rot (Sclerotinia sclerotiorum)
This disease causes serious loss in the field, storage, under transit and market conditions. The infections begin as circular water soaked areas, which become soft and watery as the disease progresses, and damage the entire cabbage head.
Control: Avoid planting cabbage and other susceptible crops in fields infested with white mold. Mechanical injuries to cabbage heads during harvesting operations should be avoided.
Black rot (Xanthomonas campestris pv. campestris)
The infected tissue turns brown and dies, and severely affected leaves drop off. The infected stems and roots become black. The heads of the infected plants remain small and its quality is reduced making it unfit for consumption.
Control: Avoiding continuous cropping of crucifers in the same field and use of resistant varieties offer good control. Treat the seeds with agrimycin-100 (100ppm) or streptocycline (100ppm).
Downy mildew (Perenospora parasitica)
Small, light green-yellow lesions on the upper leaf surface, later a grayish white moldy growth is developed on the undersurface of the leaf, and the leaf eventually becomes papery and die. Cabbage heads develop sunken black spots.
Control: Removal of weeds and alternate hosts and spraying with copper oxychloride (0.3%) are effective in controlling the disease.
Leaf spot and blight (Alternaria brassicae and A. brassiciola)
Small dark yellow spots appear on the leaf surface, which later enlarge to form circular areas with concentric rings surrounded by yellow halos. In severe cases, the entire plant defoliates.
Control: Use of disease free seeds, practicing proper crop rotation and seed treatment with hot water (50° C for 30 minutes) helps to minimize the disease incidence.
Yellows or fusarium wilt (Fusarium oxysporum f. sp conglutinans)
Initially the lower leaves and later the upper leaves turn yellow, wilt and die. With time, the dead leaves turn brown and the affected tissue becomes dry and brittle.
Control: Use of resistant varieties and very early sowing of cabbage can minimize the disease incidence.
Black leg (Phoma lingum)
Irregular spots develop on leaves and stem, which extend below the soil surface, causing black rot of lower stem and roots. Severely affected plants remain stunted and finally wilt, and under favourable condition the disease causes severe yield loss.
Control: Use of disease free seeds and hot water treatment of seeds is recommended to control the disease.
Club root (Plasmodiophora brassicae)
Roots of the infected plants develop club like swellings. Plants infected in the nursery get killed, whereas those attacked at a later stage wilt in hot weather but partly recover at night. Finally leaves become stunted, yellowish and prematurely bolt in hot weather.
Control: Crop rotation of more than 6 years and mixing finely ground limestone before planting help to reduce disease incidence.
Damping off (Pythium debaryanum)
Seedlings develop lesion near the collar region and tissue beneath become soft due to which seedling collapse and die.
Control: Seed treatment with Trichoderma viride (3-4 g/kg of seed) or thiram (2-3 g/kg of seed) and soil drenching with dithane M 45 (0.2%) or bavistin (0.1%) afford protection against the disease.
Cabbage is ready for harvest at 90-120 days after planting. Harvest the crop promptly when the heads are firm and mature, as delayed harvest can result in split heads and disease incidence. However, harvesting immature heads reduces yield, and they have shorter shelf life than mature heads, as they are too soft to resist handling damage. The heads are to be harvested by bending it to one side and cutting it with a knife. Do not snap or twist the heads to remove them as this practice damages the head and results in inconsistent stalk length. Broken stalks are also more susceptible to decay. The stalk should be cut flat and as close to the head as possible, yet long enough to retain two to four wrapper leaves. Extra leaves act as cushions during handling and may be desired in certain markets. Since the heads do not attain maturity uniformly, harvesting should be done in stages based on maturity. Average yield of cabbage for early varieties is 25-30 t/ha and that of late type is 40-60 t/ha. Place the cabbages on a rack made of wood or chicken wire, do not stack them on the ground. Mature cabbages with a good firm heart, and in good condition, can be stored in a cool, airy frost proof condition for several weeks.