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Vegetables

Onion

Allium cepa

Onion
Photo: Colin · CC BY-SA 3.0 · Wikimedia Commons

A kitchen staple sown in autumn and planted out in late winter.

Light
Full sun (6 h or more)
Height
0.4–0.5 m
Watering
Low: every 7–15 days, drought-tolerant
Soil
loose and well-drained
Edible?
Yes: the bulb
How to plant
Sow in trays 1 cm deep; plant out at 4–6 leaves, 12 cm apart.
Care
Go easy on nitrogen late on or it won't store. Lift when the leaves flop.

Calendar by climate

Warm coast
Mild Mediterranean
Southern interior
Continental interior
Cold interior and uplands
Atlantic
Canary Islands (subtropical)
SowPlantHarvestPruneFeedTreat

Dates are for growing outdoors. You can start seedlings earlier indoors or in a greenhouse, but plant them out only once the frosts are over.

Feeding and doses

Mild Mediterranean

  • Organic granular fertiliserFeb50–80 g / m²

Pest prevention and doses

Mild Mediterranean

  • Blight & downy mildewCopper (Bordeaux mixture) · Apr10–15 g / L

Approximate doses: always follow the product label. Spray in the evening, never in full sun or on flowers visited by bees. No sulphur above 30 °C.

How easy to grow by climate

  • Warm coastEasy
  • Mild MediterraneanEasy
  • Southern interiorEasy
  • Continental interiorEasy
  • Cold interior and uplandsEasy
  • AtlanticNeeds regular careRain and humidity: fungal disease
  • Canary Islands (subtropical)Easy

Plants in the same category

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