March is the beginning of autumn, and gateway to winters to be approached in a couple of months. There are some seasonal changes you can notice like shortening of days and a bit milder morning and evening hour’s temperature.
From this month all summer season vegetables start wilting as their life cycles are on the verge of ending. This time vegetable gardeners should clean up the area for winter vegetables.
Crop Rotations
Rotation means planting of next vegetable on the same piece of land or bed when the first crop is over. The scientific reasons of rotation are not only balancing the texture and fertility of soil but also protect crops against some common diseases and pests. Those vegetables having common diseases and pests should not be repeated on the same bed, for example, crops like potato, tomato, eggplants, chillies, peppers and capsicums are never to be repeated on the same bed due to identical disease and pests. Other points like heavy feeder followed by light feeder vegetable for example sweet corn is the best choice after potato crop, deep rooted vegetables by shallow rooted vegetables, legume or pulses vegetables by non legume or pulses vegetables. For example tomato, egg plant, chillies, capsicums, beans, should be replaced by winter crops like cabbage, cauliflower, broccoli, onion and garlic. We can likewise make other combinations keeping the principles of rotation in mind.
Winter Vegetables
Winter vegetables are cole crops like cabbage, cauliflower, broccoli, Brussels sprout, khol rabi or knol khol, green vegetables like spinach, bok choi, mustard, fenugreek, salad crops like Chinese cabbage, leek, coriander, underground vegetables like potato, radish. Onion, garlic, turnips, pod vegetables like garden peas, broad beans, runner beans and some miscellaneous vegetables which by an large are grown year round like beet root, lettuce, silver beet, and spring onion.
Vegetables are of two types. The First type are direct sown vegetables like spinach, bok choi fenugreek, mustard, radishes, turnips, coriander, potato, onions, garlic, garden peas and broad beans, and beet roots . The second type of vegetables is transplanted after raising plants in small area or nursery.
Nursery Raising
Nursery raising is a simple but slightly professional job, need proper attention. Select small, full sunny area or wide shallow containers for raising nursery plants. Fill with seed raising soil mixture, available in the market. Get the soil well moist but not wet for sowing. I strongly advise line sowing by placing seeds half to one cms deep with nicely covering with sand or a thin layer of fine soil.
Direct sowing and transplanting
The beds have to be cleaned from all leftover of previous crops, followed by light irrigation. Add 4 to 5 kg well rotten good quality of compost. Deep hoeing and levelling should be followed to mix up compost thoroughly. The beds are now ready for sowing and transplanting. You always follow lines or rows for sowing and transplanting to facilitate your day to day operations like weeding, hoeing, thinning, top dressing and even picking or harvesting.
Line to line and plant to plant distances vary from crop to crop, depending upon size and root zones of plants. The idea is to allow their uninterrupted growth without competing each other.
The line to line distances are almost same, 30-40 cm in all directly sown vegetables like spinach, bok choi, fenugreek, mustard, radish, coriander, beet root, onion and garlic and plant to plant distances may be around 10 cm which can be maintained after germination and subsequent thinning. In potato, the line to line distances, of course, may be 50-60 cms and plant to plant may be 15- 20 cms. Similarly transplanted vegetables like cauliflowers, cabbage, broccoli, Brussels sprout need 50-60 cms line to line and 40 cms from plant to plant distance.
Plant Protection
From initial stage to late stage of plant growth some insect and diseases are common. They are both sucking type like white fly, aphids and chewing type like slugs, snails, caterpillars and beetles are main insects. Diseases like powdery, downy mildews and blights are common in winter vegetables. They are fungal diseases. In all cases don’t wait for them to occur but take preventive measures at the initial stage of plant growth and not to allow them to invade by using suitable pesticides.
Dr Upendra Saklani is PhD Horticulture and former Head of the Department of Uttarakhand University, India