Plant: March to mid June
Harvest: year-round
Onions are easy to cultivate, grow quickly and don't require a lot of work. The number you plant leads to a relatively moderate yield, but they can be sown regularly throughout the growing season and are as a result ideal for medium-sized home gardens and allotments.
Sowing
Sow large onions in March. Spring onions should be sown from the start of April at fortnightly intervals until mid-June, ensuring a continuous supply through summer.
Onions should be planted in ground free from shade.
Set aside a section of garden - either a row one or two metres wide, or a plot - and dig the soil to a depth of about 30cm, forking in any organic matter such as manure a week before planting. Remove stones and other hard debris, then tread or pat the soil down the day before you're thinking of planting the vegetables.
Start by digging a couple of rows, only 2cm deep and spaced 30cm apart, and then place your onion sets (they look like tiny versions of the full-grown bulb) 10cm or so apart, facing upwards. Alternatively, create drills (lightly dug-over rows of soil) and then use a dibber or trowel to place the sets 2cm deep, covering them over once you've done so. Ensure that the tips of the onion sets are appearing above the soil.
The best way to grow onions is by buying a number of what are known as "onion sets" - tiny, part-grown onions which you can rear to harvestable levels yourself. You should think about planting onion sets in March, when the soil is moist but not clingy. Salad onions should be grown in spring and summer - April is an ideal time to start.
Growing
Water all of the onions you plant with rainwater as the soil becomes dry; they will need to be moist while they grow. Keep the rows free from weeds.
Harvesting
Onions can be harvested throughout the year, depending on type.
Once the foliage that appears starts to go brown and dry, wait a week or so, then pull your onions up after loosening them with a fork. Leave them to dry in the sun and then transfer to a box in a dark place; they should keep for a month or so.
As soon as spring onions look ready to eat, pull them up and eat them quickly. Replant your main crop of onions frequently and you will have plenty to store well into autumn.
Varieties to try
- Rijnsburger - golden colour, stores well
- Kamal - great tasting red onion
- Lisbon - a reliable spring onion
