The seasonal secret to harvesting fresh spring onions by the spring equinox
While most gardeners wait for summer, you can enjoy tender, white-stemmed salad onions as early as March. By mastering the timing of sowing and the choice between seeds and sets, you can transform your garden into a reliable source of early-season flavor.
The name 'spring onion' is a historical nod to their role as a vital bridge between crops. Before modern logistics, they were often the only onions available in the spring, filling the gap between the exhaustion of old stores and the maturation of new harvests. Varieties specifically bred as 'salad onions' are prized for their firm leaves and white stems, harvested before they develop into bulbs.
Success depends heavily on your starting point. Growing from sets—small, immature bulbs—is the fastest and easiest method, though they are more prone to bolting, which diverts energy from the bulb to flower production. Using heat-treated sets can mitigate this risk. Conversely, growing from seed offers a wider variety of flavors and is more cost-effective, but requires more intensive care. Note that onion seeds lose viability relatively quickly, with germination rates declining after just one or two years.
Timing is the most critical mechanism in the onion lifecycle. To enjoy greens by the spring equinox, one can sow salad varieties, such as White Lisbon Winter Hardy, as early as late August. If you sow in the spring between February and April, expect a harvest in May or June. For larger bulbs, the goal is to ensure plants are growing vigorously by late spring, as lengthening days trigger the formation of the bulb itself. For the best results, ensure your soil is well-drained and enriched with well-rotted organic matter or manure to support their limited root systems.
Source: Spring Onions from Seed to Harvest
