Onion
Allium cepa L. v cepa
Temperature
12°C to 25°C
Rainfall
314mm to 678mm per season

Conditions
What it needs
Soil
Well-drained loam, firm underneath and fine on top. Onions do badly in a rough or cloddy seedbed.
Water
Steady water while the bulbs fill, then dry weather to cure them. Rain at harvest is what ruins an onion crop.
What you will need
Tick what you already have; Grow carries the rest into the cost working.
Grow holds no supplier listings and no local prices, so it cannot tell you where to buy these or what they cost near you. Ask at your nearest agrodealer or extension office, then put those figures into the planner.
Through the season
Stages
- 01
Nursery
40 days- Sow in a clean bed
- Water and shade
- 02
Land preparation
7 days- Prepare fine, firm beds
- Work in compost
- 03
Transplanting
3 days- Transplant seedlings
- Water in
- 04
Bulb development
60 days- Weed carefully
- Keep water even
- 05
Maturity and curing
21 days- Stop watering as tops fall
- Cure in dry air
Watch for
Common problems
Purple blotch
- What you will see
- Purple-centred lesions on leaves, worst in humid weather.
- What to do
- Space for airflow, rotate away from onions, and remove affected leaves.
Thrips
- What you will see
- Silvery streaks on the leaves and stunted bulbs.
- What to do
- Worst in dry heat. Keep the crop watered, remove weeds, and ask an extension officer before spraying.
Neck rot in storage
- What you will see
- Soft, grey rot spreading from the neck of stored bulbs.
- What to do
- Cure fully in dry air before storing, do not store bulbs with thick necks, and keep the store airy.
Follow the label for doses, and ask an extension officer or vet before using a chemical you have not used before.