How to Grow Onions
The onion is probably one of the most widely grown and eaten vegetable, and forms a major part of many cuisines across the globe. This pungent bulb is available in numerous varieties including maincrop, red, Spanish, chives and spring onion and can be eaten raw or cooked. It forms the basis of many basic and complex recipes, and adds enormous flavour to any dish.
The onion, a member of the allium family, along with leeks, garlic and shallots, is extremely easy to grow and takes up little room in the garden. One main advantage to growing your own onions is that they can be stored for up to several months and therefore will last through the whole of the winter without deteriorating.
Soil conditions for growing onions
Onions can more or less grow in any type of soil, although they have a preference for a well drained, rich but light earth with a pH of between 5.5 and 6.5, which is slightly acidic. A firm, compact soil is an absolute must when growing onions.
Climate conditions for growing onions
Onions are resistant to frost and therefore can be planted earlier than most crops, yet they still prefer to grow in a sunny position that receives at least 6 hours of direct sunlight a day.
Soil preparation
The soil should be prepared at least 2 months before planting for the best results. This can be done in December when there are less tasks to carry out in the garden. Dig a bed approximately half a metre deep and work in plenty of well-rotted manure or other organic material. Clear the ground, removing stones and other unwanted matter.
A few weeks before planting the seeds, work the area again with a rake, adding some general fertiliser and then treading down the soil with your feet to make it firm and compact. Lightly rake again so that the soil is crumbly and light on top.
A few weeks before planting the seeds, work the area again with a rake, adding some general fertiliser and then treading down the soil with your feet to make it firm and compact. Lightly rake again so that the soil is crumbly and light on top.
Planting the onion seeds
Onion seeds can be planted in March or if using a cloche, in February for an August or September harvest. The soil should be moist but not soaking wet.
Sow the onion seeds 1 inch apart and ½ inch deep into drills or thin farrows. Rows should be about 9 inches apart. Cover the seeds lightly with soil and water. Germination will take place within 21 days when you will see the appearance of the tiny seedlings above the soil.
Sow the onion seeds 1 inch apart and ½ inch deep into drills or thin farrows. Rows should be about 9 inches apart. Cover the seeds lightly with soil and water. Germination will take place within 21 days when you will see the appearance of the tiny seedlings above the soil.
Thinning out the onion seedlings
Once the onion seedlings have pushed through the soil, they will have to be thinned out in order for them to grow.
Once the seedlings are standing vertically at a height of 2 inches (5cm), remove the weakest plants so that there is a space of 1 - 2 inches (2½ - 5cm) between the stronger ones and then again to 5 inches (12½cm) apart at a later time.
Onions, similar to cucumbers and tomatoes do not like their roots to be disturbed, therefore remove the weaker plants with care using garden scissors or secateurs.
Ensure that weeds are kept at bay by hoeing or by removing by hand on a regular basis.
Once the seedlings are standing vertically at a height of 2 inches (5cm), remove the weakest plants so that there is a space of 1 - 2 inches (2½ - 5cm) between the stronger ones and then again to 5 inches (12½cm) apart at a later time.
Onions, similar to cucumbers and tomatoes do not like their roots to be disturbed, therefore remove the weaker plants with care using garden scissors or secateurs.
Ensure that weeds are kept at bay by hoeing or by removing by hand on a regular basis.
Watering the onion seedlings
It is extremely important that the onion seeds receive water throughout the growing process. The soil should be moist at all times and if it isn't then you must water it. Do not saturate though or over-water as this could lead to disease in the form of fungus or rot. The onion seedlings should receive an average of 1 inch of water per week.
Water your onion plants up until mid-August and then stop. The onions should not receive water after this point, as from then on they need to ripen and mature.
Water your onion plants up until mid-August and then stop. The onions should not receive water after this point, as from then on they need to ripen and mature.
Fertilising the onion seeds
The soil should have been fertilised before planting by adding manure or compost but a nitrogen liquid fertiliser should also be applied during the growing season. Add fertiliser about 5 weeks after initial planting.
Mulch should also be added to retain moisture within the soil and to keep weeds at bay. Do not cover the bulbs when they are growing as they need sunlight to mature.
Mulch should also be added to retain moisture within the soil and to keep weeds at bay. Do not cover the bulbs when they are growing as they need sunlight to mature.
Harvesting the onions
The onions are ready to harvest 1 - 2 weeks after the foliage has turned a yellowy brown, dries up and when the tops topple over. Carefully ease the bulbs from the soil by hand or with a fork.
Remove all the dirt from the onions and leave them to dry or cure in the sun for several days.
Once the onions are dry, remove the tops by cutting about 1 inch (2½cm) above the top of the onion and also remove the roots. Leave to dry and then store in a cool, dark and dry place.
Remove all the dirt from the onions and leave them to dry or cure in the sun for several days.
Once the onions are dry, remove the tops by cutting about 1 inch (2½cm) above the top of the onion and also remove the roots. Leave to dry and then store in a cool, dark and dry place.
Onion pests
Watch out in particular for onion fly and eelworm. If you see signs of infection carefully remove the infected plants and dispose of them. It is possible to contain the infection without it spreading to all of the plants.
Onion disease
Neck rot occurs when onions are being stored, so you must check them regularly and remove those that have a grey fungus or rot at the neck.
White rot is a serious fungal growth that turns leaves yellow and rots the bulbs. The diseased bulbs must be removed from the ground and destroyed.
White rot is a serious fungal growth that turns leaves yellow and rots the bulbs. The diseased bulbs must be removed from the ground and destroyed.
