- Brussels Sprouts
- Cole Crops
- Heirloom Vegetables
- Peas - Southern
- Root Crops
- Seed Tape
- Sweet Potatoes
- Perennials, Bulbs & Flowers
- Trees & Shrubs
- Gardens Alive! & Supplies
- New This Season
- Gurney's Choice
- Niles' Favorites
- Only From Gurney's
- Deer Resistant Plants
- Holiday Gift Ideas
Onion Sets & Plants from Gurney's
Onion Sets & Plants FAQ's
How to choose an onion set or plant for your garden
When selecting onion varieties, keep these things in mind: how you want to use the onions, how much daylight you have, and whether you want onion sets, onion plants or onion bulbs. Use our zone finder information and recommendations to ensure successful gardening.
Types of Onions
Some onions are best for eating fresh and known for their sweetness. Storage onions tend to be more pungent, but can keep for months, often over winter.
Daylight and Onions
Onion are classified as long day, short day and day neutral. Long-day onions need 13-16 hours of daylight and do best in the northern zones; short-day onions do best in the southern zones and thrive in regions with a mild winter climate; and day-neutral onions grow well in most zones.
Onion Sets, Onion Plants or Onion Seeds
You can grow onions from onion plants, onion sets or onion seeds. Onion plants are the fastest way to grow onions; onion sets (dormant onion bulbs) are the most popular because they're quick and easy to grow; and onion seeds are the most economical but take the longest to grow.
Onion Plants & Sets: Getting the Most out of Your Purchase
While onions are easy to grow, they require plenty of direct sunlight (at least 6-8 hours of direct sunlight daily) and well-drained soil. They're also heavy feeders, and we recommend fertilizing with Gurney's Onion Food, an all-natural, slow-release fertilizer.
Getting Started with Onion Plants and Sets
The keys to growing onions are to take into account their growing conditions, plant them correctly and give them a little care.
How to Plant Onion Sets and Plants
To plant onion sets (dormant bulbs), plant 1-2 in. deep and space 2-3 in. apart. Water well. Once the plants are growing, thin so they are 3-4 in. apart. Use the ones you thin as green onions. If planting onion plants, keep the same spacing as onion sets, but plant so that the roots and 1 in. of the plant are below the soil line. Water well.
When to Plant Onion Sets or Plants
Onion sets or plants can be planted in early spring as soon as the soil can be worked. They can be planted as a fall crop for green onions.
How to Grow Onion Plants
Once your onions start growing, control the weeds around the plants and fertilize twice with Gurney's Onion Food.
When to Harvest Onions
Onions can be harvested at the immature or green onion stage throughout the growing season. However, if you're planning to store them, allow the tops of the onions to wilt (usually 3-4 months after planting). Pull or dig the bulbs from the soil. Cut the tops from the bulb and allow the bulbs to cure in a shady, dry place.