Onion

Allium cepa, Stuttgart Long Keeper from Kings Seeds

Germinates in soil temperatures of 10-25°, direct sow 15cm apart and 2cm deep, takes 10 to 14 days to germinate, then 26 weeks to harvesting – so I must get these in the ground ASAP by the end of September, and it's too late now to do two sowings which would otherwise have been a nice idea. Apparently they want a long cool spring period to maximise the top growth before the bulbs start to swell in summer.

Onions need a well-composted sunny spot with good air circulation as they are prone to fungal diseases in damp conditions. On the companion planting front, they are good with strawberries and lettuce (and beneficial for carrots), but bad with peas and beans.

At harvest time the leaves should yellow and die down, after which the bulbs can be carefully lifted out with a fork (important to avoid bruising) in a dry breezy period and left to dry on a wire rack in the sun for a couple of days. The necks have to thoroughly dry out (up to two weeks) before storing.

While I grew some spring onions last year, onions themselves will be a new experiment this year. The Stuttgart Long Keeper is an heirloom variety, and I intend to plant a long row in the long triangular stretch (maybe 3 metres long) leading up to the lemon tree shown in my post of 31 August. I did compost this spot in autumn, so hopefully it'll prove to be suitable soil (nothing's ever been grown in it except weeds).