Onion Marco is a maincrop variety with excellent storage capabilities, often staying in good condition until March. The thin necked, straw coloured round bulbs of Onion Marco grow to a good size in most soils and have a good disease tolerance.
Sow seeds mid March to April. Sow seeds thinly, 1cm (2in) deep, in drills 30cm (12in) apart.
When large enough to handle, thin seedlings to 7-10cm (3-4in) apart for medium sized bulbs, or slightly wider spacing if larger bulbs are required.
Keep well watered during dry weather especially during early stages of growth as the bulb swells. Do not bend leaves over, just wait for them to yellow and wither naturally, then lift bulbs on a sunny day and leave on soil surface to dry.
Store sound and unblemished bulbs in trays or used tights in a dry, airy but frost-free site for use throughout the winter.
For years onions have been used as one of the oldest medicines for their anti-bacterial, antiseptic and anti-asthmatic properties. They have also shown to lower blood pressure and cholesterol levels.