How Long Do Onions Take to Grow? A Complete Guide
Onions are one of the easiest and most rewarding vegetables to grow, but they require patience. Whether you’re planting from seeds, sets, or transplants, knowing how long onions take to grow helps you plan your garden efficiently.
So, how long does it take to grow onions?
✔️ From seeds: 100-150 days
✔️ From sets: 60-80 days
✔️ From transplants: 75-90 days
In this guide, we’ll cover:
✔️ Onion growth timelines based on planting methods
✔️ The different stages of onion growth
✔️ Tips for a faster, healthier onion harvest
Let’s get started! ??
How Long Does It Take to Grow Onions?
1️⃣ Growing Onions from Seeds (100-150 Days)
✔️ Takes the longest time but offers the widest variety options.
✔️ Requires indoor sowing or a long growing season.
✔️ Best for patient gardeners looking for unique onion varieties.
? Planting to harvest: 3.5 to 5 months
2️⃣ Growing Onions from Sets (60-80 Days)
✔️ Easiest and fastest way to grow onions.
✔️ Onion sets are small, pre-grown bulbs that mature quickly.
✔️ Less risk of pests and diseases.
? Planting to harvest: 2 to 2.5 months
Tip: Onion sets are great for beginners who want a quick and easy harvest!
3️⃣ Growing Onions from Transplants (75-90 Days)
✔️ Young onion plants started indoors or bought from nurseries.
✔️ Faster than seeds but slower than sets.
✔️ Best for consistent, uniform onion growth.
? Planting to harvest: 2.5 to 3 months
Onion Growth Timeline: From Planting to Harvest
| Growth Stage | Timeframe | Description |
|---|---|---|
| Germination (Seeds Only) | 7-14 days | Seeds sprout tiny green shoots. |
| Seedling Stage | 2-4 weeks | Leaves start growing, roots develop. |
| Bulb Formation | 2-3 months | Onion bulbs start swelling underground. |
| Maturity & Harvest | 3-5 months | Onion tops turn yellow, ready for harvesting. |
Fact: Onion growth time varies based on climate, variety, and soil conditions.
Best Time to Plant Onions
✔️ Spring planting (most common) – Plant in March-April for a summer harvest.
✔️ Autumn planting (overwintering onions) – Plant in September-November for an early summer harvest.
? Day-Length Types:
- Short-day onions (best for Southern regions) – Planted in fall, harvested in spring.
- Long-day onions (best for Northern regions) – Planted in spring, harvested in summer.
Tip: Choose onion varieties suited to your climate for the best results!
How to Grow Onions Faster
? Choose the right variety – Some onions grow faster than others.
? Water consistently – Keep the soil evenly moist.
☀️ Provide full sun – Onions need 6+ hours of sunlight daily.
? Thin seedlings properly – Prevents overcrowding and improves bulb size.
? Feed with nitrogen fertilizer – Helps onions grow bigger, faster.
Tip: Stop fertilizing when bulbs start forming—this encourages onion swelling instead of leaf growth.
When Are Onions Ready to Harvest?
✔️ The tops turn yellow and fall over naturally.
✔️ Bulbs are fully developed and firm.
✔️ Outer skin starts drying and papery.
? Spring onions (green onions) can be harvested after 6-8 weeks for fresh use.
? Mature onions take 2-5 months, depending on how they were planted.
Tip: After harvesting, cure onions for 2-3 weeks in a dry, well-ventilated area for long-term storage.
Frequently Asked Questions (FAQs)
How long does it take for onions to grow from seeds?
✔️ 100-150 days, depending on variety and growing conditions.
What is the fastest way to grow onions?
✔️ Onion sets take only 60-80 days and are the quickest method.
Can I grow onions in containers?
✔️ Yes! Use a deep container (at least 6 inches) and space onions 4 inches apart.
How do I make onions grow bigger?
✔️ Water consistently, thin seedlings, and use nitrogen fertilizer early in growth.
When should I stop watering onions before harvest?
✔️ Stop watering 2 weeks before harvesting to allow bulbs to dry.
Final Thoughts: How Long Do Onions Take to Grow?
✔️ Onions take 2-5 months to grow, depending on the planting method.
✔️ Seeds take the longest (100-150 days), while sets are the fastest (60-80 days).
✔️ Proper watering, fertilizing, and spacing help onions grow faster.
✔️ Harvest when the tops fall over and cure for long storage.
Now you’re ready to grow your own onions! Which method will you try? Let us know in the comments! ??