Onion Sets vs Seeds vs Transplants: How to Plant Onions
Comparing onion sets, seeds and transplants, how deep and far apart to plant, growing onions in raised beds and containers, and regrowing onions from scraps.
You can grow onions from sets (small bulbs), transplants (young plants) or seed. Sets are easiest; transplants give reliable large bulbs; seed is cheapest and offers the widest variety choice.
Comparison
| Sets | Transplants | Seed | |
|---|---|---|---|
| Ease | Very easy | Easy | More work |
| Time to harvest | Fastest | Fast | Slowest |
| Bolting risk | Higher with large sets | Low | Low |
| Variety choice | Limited | Medium | Widest |
| Cost | Medium | Medium–high | Lowest |
Planting Depth and Spacing
- Sets: 2–3 cm deep, tip just showing, 10 cm (4 in) apart.
- Transplants: 2–3 cm deep, 10–15 cm (4–6 in) apart; trim long roots and tops slightly.
- Seed: 1 cm deep, thin to 10 cm.
- Rows 30 cm (12 in) apart, or a grid of 10–15 cm in raised beds.
Choose small sets (about 1–2 cm across): large sets bolt more easily.
Containers and Grow Bags
Use containers at least 25 cm (10 in) deep with drainage, rich potting mix, full sun and 7–10 cm spacing. Water evenly; containers dry out quickly.
Regrowing From Scraps
Planting an onion root end regrows green tops you can harvest as scallions, but rarely a full new bulb.
More Onion Guides
- How to Grow Onions: The Complete Guide
- Why onions bolt
- When to harvest and cure onions
- How to store onions
Frequently Asked Questions
Are onion sets or seeds better?
Sets are easier and faster; seeds give more varieties and fewer bolting problems.
How deep do you plant onion sets?
About 2–3 cm, with the tip just above the soil.
TarlaTapan guides focus on practical, field-tested growing advice. Corrections and suggestions are welcome at info@tarlatapan.tr.