How to Sow Long Brown Onion Shallot Seeds in the UK
Long Brown Onions, also known for their slim elliptical shape, are an early-maturing variety with a sweet and mild flavour. These onions are easy to peel and slice, making them a favourite for reducing waste in the kitchen. Ideal for growing in UK gardens, greenhouses, or allotments, these onions not only provide a good yield but also offer excellent storage capabilities, ensuring you have fresh onions on hand for months. This comprehensive guide will walk you through the steps to successfully sow and grow long brown onions from seed in the UK, providing answers to commonly searched questions.
- Indoor Sowing: To give your onions a head start, sow seeds indoors from late winter to early spring (February to April). This method is especially beneficial for UK gardeners in regions with shorter growing seasons or unpredictable weather. Use seed trays filled with fine seed compost to ensure healthy root development.
- Outdoor Sowing: Direct sowing can begin from late March to early April when the soil has started to warm. Avoid waterlogged or cold soil as this can hinder seed germination. Outdoor sowing is a great option if you prefer a more natural growing process without transplanting.
Soil Preparation and Sowing Instructions
- Ideal Soil Conditions: Long brown onions thrive in well-drained, fertile soil with a neutral to slightly acidic pH (6.0-7.0). Adding well-rotted compost or organic matter to your soil a few weeks before planting will provide the nutrients onions need for robust growth.
- Sowing Depth: Sow seeds at a depth of 6-8 mm (1/4 to 1/2 inch). Make sure to plant in rows approximately 30 cm (12 inches) apart to provide ample space for growth.
- Seed Spacing: Scatter seeds thinly, aiming for around 4-5 cm (1.5-2 inches) between plants after thinning. This spacing ensures your onions have enough room to develop without competing for nutrients.
Germination and Temperature Requirements
- Germination Time: Under optimal conditions (soil temperature between 10-21°C), you can expect seeds to germinate within 7-21 days. Keep the soil consistently moist but not waterlogged during this period to encourage successful germination.
- Temperature: Long brown onions prefer a mild climate, so keeping temperatures between 10-25°C during germination will yield the best results. Cover the seed tray with a clear plastic cover or propagator to maintain warmth and humidity if sowing indoors.
Growing and Caring for Long Brown Shallot Onions
- Thinning: Once your seedlings reach about 5-8 cm (2-3 inches) tall, thin them out to the final spacing of 4-5 cm between plants. Thinning prevents overcrowding and promotes larger, healthier onions.
- Watering: Water your onion plants regularly, especially during dry periods, but avoid waterlogging the soil. As onions approach maturity, reduce watering to allow the bulbs to harden off, improving their storage capability.
- Sunlight: Plant your onions in a location that receives full sun. Onions need at least 6-8 hours of direct sunlight daily for optimal growth.
Harvesting and Storage
- Harvest Time: Long brown onions take around 120 days from sowing to harvest. Harvest them when the tops begin to yellow and fall over naturally. This indicates that the bulbs have reached full maturity.
- Storage: After harvesting, allow the onions to cure by placing them in a warm, dry, and well-ventilated area for 2-3 weeks. Once the outer skins have dried, store the onions in a cool, dry place, and they will keep for several months.
Common Questions for Growing Long Brown Shallot Onions
Do I need to fertilise onions? Onions benefit from a well-prepared, fertile soil but do not require heavy fertilisation. Adding organic compost or a balanced fertiliser before sowing will give them a good start.
Can onions grow in partial shade? While long brown onions prefer full sun, they can tolerate light shade. However, planting them in full sun will yield larger and sweeter bulbs.
What pests and diseases should I watch out for? Onions are relatively pest-resistant but may be affected by onion fly or downy mildew in wet conditions. Ensure good air circulation and avoid overhead watering to prevent mildew.
By following these guidelines, UK gardeners can enjoy a bountiful harvest of sweet, flavourful long brown onions that are perfect for storing and using throughout the year. Whether grown in containers, raised beds, or directly in the ground, these onions are a versatile and rewarding crop for any garden.
