Vegetable · Amaryllidaceae (onion family)
Pyaz · प्याज़ · Allium cepa
Every leaf it grows becomes one ring of the bulb.
Rabi onion is the crop that stores. Seedlings are raised in a nursery in October–November, transplanted in December–January and harvested in April–May. Bulbs from this crop keep for months and supply the market until the next harvest, so a well-cured rabi crop often earns the best price.
Bulb bulking · roots shown through the soil
At a glance
Leaves grow best in cool weather (13–24 °C). Bulbs form when days get longer and warmer (25–30 °C) in March–April. A long cold spell on big seedlings can make them bolt (send up a flower stalk).
Nursery sowing
15 Oct – 20 Nov
Transplanting
15 Dec – 20 Jan
Harvest
15 Apr – 31 May
160–190 days from sowing
Temperature
13–25 °C to grow
15–25 °C at sowing
Soil
Friable sandy loam or silt loam, rich in organic matter and well drained
pH 6–7.5
Seed rate
3.2–4 kg/acre
8–10 kg/ha
Spacing
15 × 10 cm
2–3 cm deep
Irrigations
10–15
3 critical stages
Yield
101–142 q/acre
250–350 q/ha
Season
Heavy clay gives misshapen bulbs and is hard to dig. Avoid saline and waterlogged land.
Seed to harvest
Scroll through the season. The plant in the glass tank grows to each stage — roots and all — and every card says what the crop is doing and what you should do in the field that week.
Stage 1 of 7
Nursery sowing
Day 0–7
Seeds in the raised nursery bed take up water and swell.
Your job · Sow treated seed thinly in lines, cover with fine FYM and straw, and water lightly.
A thin green shoot comes up bent like a loop (the 'flag'), then straightens.
Your job · Remove the straw cover, water lightly and watch for damping-off.
Seedlings grow 3–4 leaves and reach pencil thickness.
Your job · Harden seedlings by cutting water a week before, then transplant at 15 × 10 cm and irrigate at once.
The plant builds 8–12 leaves. Each leaf base later becomes one ring of the bulb, so more healthy leaves mean a bigger onion.
Your job · Top-dress nitrogen at 30 and 45 days after transplanting, weed regularly and scout for thrips.
As days lengthen and warm up, the leaf bases begin to swell into a bulb.
Your job · Stop nitrogen, keep soil evenly moist and spray for thrips or purple blotch if seen.
Bulbs grow fast and the neck starts to soften.
Your job · Irrigate every 7–8 days and keep the field weed-free.
Tops bend and fall over and leaves turn yellow. The bulb skin colours up.
Your job · Stop irrigation 10–15 days before. Pull bulbs when about half the tops have fallen.
The seed
Use certified seed of a variety bred for your region, at the right rate, and treat it before sowing.
One seed
≈ 3 mm
Seed rate
3.2–4 kg/acre
8–10 kg/ha
1000-seed weight
3.5 g
Field & sowing
Transplanting nursery seedlings on small flat beds
Layout
Flat beds
Row to row
15 cm
Plant to plant
10 cm
Depth
2–3 cm
Feeding the crop
These are the standard doses for a medium-fertility field. Your Soil Health Card can raise or lower them — test first, then feed.
Nutrient dose
Plus 20 t/ha (8.1 t/acre) of well-rotted farmyard manure or compost.
For 1 acre of Onion
What to buy
Urea
1.5
bags · 71 kg
DAP
1
bag · 44 kg
MOP
1
bag · 40 kg
Nutrients in it: N 40 kg · P₂O₅ 20 kg · K₂O 24 kg
Also add farmyard manure or compost: 8.1 t
Not yet checked against a package of practices. Confirm the dose with your KVK before you buy.
Urea has 46 % N; DAP 18 % N and 46 % P₂O₅; MOP 60 % K₂O. Urea comes in 45 kg bags, DAP and MOP in 50 kg.
Water
A crop forgives a late irrigation at some stages and punishes it at others. These are the days that decide yield.
Protection
Walk the field every week. Most problems are cheap to stop early and expensive to fix late. For any spray, follow the label dose and check with your KVK.
Signs · Tiny insects hide between leaves and scrape them, leaving silvery-white streaks. Leaf tips twist and dry. Worst in warm, dry weather from February to April.
Manage · Grow two rows of maize or wheat around the field as a barrier and put up blue sticky traps. If numbers are high, spray an insecticide such as fipronil — as per label / your KVK.
Signs · Small white sunken spots that turn purple with a yellow border; leaves bend and collapse. Spreads after rain and in humid weather.
Manage · Rotate crops and remove old onion debris. Spray mancozeb with a sticker every 10–15 days once spots appear — as per label / your KVK.
Signs · Yellow to orange streaks on one side of the leaf that turn brown; leaf tips dry back.
Manage · Balanced fertiliser, good drainage and the same sprays as for purple blotch — as per label / your KVK.
Signs · In the nursery, seedlings rot at soil level and fall over in patches.
Manage · Use raised beds and treated seed, sow thinly and avoid overwatering. Drench with Trichoderma or a fungicide — as per label / your KVK.
Signs · A flower stalk shoots up before the bulb forms; bulbs stay small with a hard, hollow neck and do not store.
Manage · Use the right variety and sowing time, and transplant 6–8-week-old seedlings — not older ones. Snap off flower stalks as soon as they appear.
Signs · One plant forms two or more bulbs inside a common skin.
Manage · Keep irrigation regular, avoid excess nitrogen and do not transplant overage seedlings.
Common · Bathua, motha, doob grass, wild oats and other winter weeds
Harvest
A good crop gives
101–142q/acre
250–350 quintal per hectare