Onion Eclipse L303 (Allium cepa) is a high-yielding, hybrid, short-day onion variety known for its uniform, round shape, firm texture, and excellent storage capacity. It has smooth, golden-brown skin with crisp, mild-flavored white flesh, making it a great choice for fresh use, cooking, and long-term storage. This variety is resistant to bolting and thrives in warm climates, making it ideal for southern growers.

How to Grow Onion Eclipse L303

Sowing and Germination

• Starting Indoors: Start seeds indoors 8–10 weeks before the last frost. Sow seeds 1/4 inch deep in well-draining soil at temperatures of 65–75°F for optimal germination.
• Direct Sowing: In warm climates, sow seeds directly in the garden when soil temperatures reach 50°F in early spring or fall for a winter crop.
• Bulb Sets: Plant onion sets 1 inch deep and 4–6 inches apart for faster growth.

Transplanting:

• Harden off seedlings for 7–10 days before transplanting outdoors.
• Space plants 4–6 inches apart in rows 12–18 inches apart for proper bulb formation.

Soil Requirements:

• Prefers well-drained, sandy, or loamy soil with a pH of 6.0–7.0.
• Enrich the soil with compost or organic matter before planting.

Sunlight:

• Requires full sun (at least 6–8 hours daily) for optimal growth.

Growing Onion Eclipse L303

Watering:

• Provide consistent moisture, especially during bulb development. Water about 1 inch per week, increasing in dry conditions.
• Avoid overwatering to prevent root rot and fungal diseases.

Mulching:

• Apply a thin layer of mulch to retain moisture and suppress weeds.

Fertilizing:

• Apply a nitrogen-rich fertilizer every 2–3 weeks during early growth to promote strong leaf development.
• Once bulbs start forming, switch to a fertilizer higher in phosphorus and potassium to support bulb growth.
• Avoid excessive nitrogen after bulb formation to prevent excessive foliage at the expense of bulb size.

Pest and Disease Management:

• Watch for thrips, onion maggots, and aphids; use neem oil or insecticidal soap as needed.
• Ensure good air circulation and avoid overhead watering to prevent fungal diseases like downy mildew and botrytis rot.
• Rotate onion crops annually to prevent soil-borne diseases.

Fast Facts

• Latin Name: Allium cepa
• Type: Hybrid, Short-Day Onion
• USDA Zones: 5–12
• Days to Germination: 7–14 days
• Days to Maturity: 100–110 days
• Sunlight: Full Sun
• Spacing: 4–6 inches apart
• Soil pH: 6.0–7.0
• Color: Golden-Brown

How and When to Harvest Onion Eclipse L303

• Harvest when tops turn yellow and fall over, usually after 100–110 days.
• Carefully lift bulbs from the soil and allow them to cure for 2–3 weeks in a warm, dry, shaded area with good airflow.
• Once fully cured, trim the roots and foliage, then store in a cool, dry place. Properly cured onions can last several months in storage.

Onion Eclipse L303 Seed Saving

• As a hybrid variety, Onion Eclipse L303 does not produce true-to-type seeds, meaning saved seeds may not retain the original plant's characteristics.
• For consistent results, it’s best to purchase fresh hybrid seeds each season.

Onion Eclipse L303 is a high-performing, disease-resistant onion variety perfect for gardeners looking for reliable, uniform bulbs with excellent storage capability. With proper care, this variety will provide a productive harvest of delicious, mild onions for months to come! 🌱