Spring Onion Seeds

Spring Onions Seeds FAQs

Take a look at some of the frequently asked questions we receive from those looking to buy Spring Onion Seeds in the UK. You can contact our Customer Service Team or browse our general FAQs for further advice.

When should I plant Spring Onion seeds?

In the UK, you can plant spring onion seeds during the early spring months, typically from March to April, as soon as the soil can be worked and temperatures start to rise. Spring onions prefer cool weather, so planting them when the soil temperature is around 10-15°C (50-60°F) is ideal for germination and early growth.

If you prefer a fall harvest, you can also sow spring onion seeds in late summer or early autumn, around August to September, for a crop later in the season.

Keep in mind that exact timing can vary depending on your specific location within the UK and local weather conditions, so it's always a good idea to monitor soil temperatures and weather forecasts to determine the best time for planting.

How do you grow Spring Onions from seed UK?

Growing spring onions from seed in the UK is relatively straightforward. Choose a sunny or partially shaded spot in your garden with well-draining soil, and amend compacted soil with organic matter like compost for improved drainage and fertility. Sow the seeds directly into the prepared soil in early spring (March to April) or late summer/early autumn (August to September), making shallow furrows or drills about 1/2 inch deep and spaced 6 inches apart.

Keep the soil consistently moist but not waterlogged, watering the newly sown seeds gently to avoid displacement. Once the seedlings emerge and reach a height of a few inches, thin them out to prevent overcrowding, spacing them about 2-3 inches apart for proper growth. Apply a balanced fertiliser about a month after sowing to encourage healthy growth, and keep the area around the spring onions free from weeds to avoid competition for nutrients and water. Harvest the spring onions when they reach the desired size, typically around 8-12 weeks after sowing, by pulling them up by hand or using a small garden trowel to loosen the soil around the bulbs.

How long does it take to harvest Spring Onion Seeds?

Harvesting spring onion seeds takes considerably longer than harvesting the green onions themselves, typically within 8-12 weeks after planting. However, if you're interested in harvesting seeds, you'll need to allow the plants to mature beyond the typical harvest stage. This involves several stages: bolting, where flower stalks emerge; flowering and seed formation, with small white flowers developing into seed pods; seed maturation, where the pods dry out over several weeks to months; and finally, seed extraction, where seeds are removed from the dried pods for storage.

Overall, the process from planting to harvesting seeds can vary depending on growing conditions and the specific variety, typically taking at least a year as the plants complete their seed production cycle.

Why Grow Spring Onions from Seed?

Growing spring onions from seed offers several advantages. When you grow from seed, you gain access to a wider variety of cultivars, enabling you to select varieties that suit your taste preferences, culinary needs, and growing conditions. Additionally, buying seeds is more cost-effective than purchasing pre-grown plants, as a packet often contains numerous seeds, providing multiple plants at a lower cost per plant. Growing from seed ensures fresher and higher quality produce, as you have control over growing conditions like soil quality, watering, and pest management, leading to better-tasting and more nutritious onions.

Where can you grow Spring Onions?

Spring onions can be grown in various areas of your garden, including garden beds, containers, raised beds, hanging baskets, cold frames, greenhouses, and even interplanted with other vegetables or herbs. Planting directly in garden beds is common; choose a sunny or partially shaded spot with well-draining soil and amend with organic matter for fertility. Containers offer flexibility for limited spaces, requiring good quality potting mix and drainage. Raised beds improve drainage and aeration, while hanging baskets utilise vertical space creatively. Cold frames and greenhouses extend the growing season, and interplanting maximises space and deters pests. Ensure adequate sunlight, water, and soil nutrients for optimal growth and harvest.

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