Blog

How to Grow Onions and Leeks: A Comprehensive Guide

Growing your own onions and leeks can be a rewarding experience whether you’re planning to harvest green onions or full-sized bulbs, or if you’re interested in cultivating leeks this guide will walk you through the essential steps for successful planting, care, and harvesting.

Planting Onions

When to Plant: January

Sunlight Requirements: Onions thrive in full sun, requiring at least 6-8 hours of sunlight per day.

Soil Preparation:

• Location: Choose a spot with extremely well-drained soil. This can be in raised beds, in-ground, or containers.
• Soil Amendment: Enrich the soil with compost such as cotton bur compost, cow, or chicken manure to improve texture and provide slow-release nutrients. Work this into the soil to a depth of 8-10 inches. Add a balanced fertilizer like Espoma Garden Tone or 10-20-10.

Planting Onions:

• Depth: Plant onions 1-2 inches deep.
• Spacing: Space bulbs 3-4 inches apart. For green onions (scallions), space them 2 inches apart. Harvest every other one in 2-3 weeks to eat as green onions, leaving the rest to mature.

Watering and Fertilizing:

• Watering: Ensure onions receive water at least once a week if rainfall is insufficient.
• Fertilizing: Begin bi-weekly feeding with nitrogen (21-0-0) three weeks after planting. Continue fertilizing until the onion bulbs start to push the soil away and cracks form in the soil. No additional fertilizer is needed once this stage is reached.

Harvesting Onions:

• Green Onions/Scallions: Harvest in 2-3 weeks when they reach your desired size.
• Full-Size Onions: Harvest in May-June when the tops start to yellow and fall over, or when the onions reach the desired size.

Curing and Storing Onions:

1. Curing: Pull the onions, shake off the excess soil, and lay them out to dry for 7-10 days with the tops still attached. Ensure they are in a dry area with good air circulation.
2. Preparation: After curing, trim the tops and roots with pruning shears. Remove as much dry dirt as possible without disturbing the papery outer skins.
3. Storage: Store onions in a cool, dry place.

Growing and Storing Leeks

Planting Leeks:

• Spacing: Plant leeks in holes 4-6 inches deep, spaced 4-6 inches apart, with rows 6-12 inches apart.
• Care: As leeks grow, mound soil around the shafts to keep them white.

Harvesting and Storage:

• Harvesting: Leeks can be harvested at any time. They are hardy and often left in the ground until needed.
• Storage: Store leeks at around 32°F and high humidity. Cool them immediately upon digging, and pack them in plastic bags to prevent drying out. Leeks can be stored this way for 2-3 months. For long-term storage, leeks can be frozen. Cook them directly from frozen for the best flavor.

By following these steps, you can enjoy a successful harvest of onions and leeks that will enhance your meals and your garden. Happy planting!