Growing onions seems simple…
Plant them, water them, wait — and harvest.
But then harvest time comes, and instead of big, firm bulbs…
👉 you get small, underwhelming onions.
If that sounds familiar, you’re not alone.
The difference between small onions and large, full bulbs usually comes down to a few key techniques — and one of the most debated is topping onions.
So does topping really work?
And what actually makes onions grow bigger?
Let’s break it down clearly.
What Does “Topping Onions” Mean?
Topping onions refers to:
👉 cutting or bending the green tops (leaves) during the growing season.
The idea behind it is simple:
👉 redirect the plant’s energy from leaves to bulb growth.
But here’s the truth…
Does Topping Onions Really Work?
👉 In most cases: No, not the way people expect.
Onion leaves are essential for:
- photosynthesis
- energy production
- feeding the bulb
👉 Cutting them too early can actually:
- reduce growth
- lead to smaller bulbs
💡 Some gardeners bend tops near harvest to speed drying — but not to increase size.
🌿 The Real Secrets to Bigger Onion Bulbs
If you want large, healthy onions, focus on what actually works:
1. Choose the Right Onion Variety
This is one of the biggest factors.
👉 There are:
- short-day onions
- long-day onions
- intermediate types
👉 Using the wrong type for your region = smaller bulbs.
2. Give Full Sunlight
Onions need:
- 6–8+ hours of direct sun
👉 Less sun = less energy = smaller bulbs.
3. Use Loose, Well-Drained Soil
Onions grow underground, so soil matters a lot.
👉 Best soil:
- loose
- rich in organic matter
- well-draining
👉 Hard soil restricts bulb expansion.
4. Feed Consistently (Especially Early)
Onions need nutrients to build strong tops first.
👉 Early stage:
- nitrogen supports leaf growth
👉 Later stage:
- reduce nitrogen
- allow bulb development
5. Water Regularly (But Not Excessively)
👉 Keep soil:
- evenly moist
- not soggy
⚠️ Irregular watering can:
- stress plants
- slow bulb growth
6. Don’t Crowd Plants
👉 Proper spacing is critical.
- bulbs need room to expand
- crowded plants compete for nutrients
💡 Aim for:
- about 10–15 cm (4–6 inches) apart
7. Start Early in the Season
Onions need time to develop.
👉 The earlier they establish:
- the bigger the bulbs can grow
8. Let the Tops Fall Naturally
👉 This is key.
When onions are ready:
- tops will bend and fall on their own
👉 That’s your signal:
- bulbs are mature
- time to harvest soon
When (If Ever) Should You Bend Onion Tops?
👉 Only near harvest.
Some gardeners gently bend tops:
- to speed up drying
- to prepare for harvesting
⚠️ But:
- don’t do it too early
- don’t rely on it for size
Common Mistakes That Keep Onions Small
- cutting leaves too early
- planting wrong variety
- poor soil
- overcrowding
- inconsistent watering
- lack of sunlight
Final Thoughts
Growing bigger onions isn’t about one trick…
👉 it’s about doing the basics right.
Topping onions might sound like a shortcut, but real results come from:
✔ proper variety
✔ good soil
✔ consistent care
Get those right, and your onions will grow bigger — naturally 🧅🔥
