If your garlic harvest produces small bulbs instead of large, full heads, something in the growing process likely limited bulb development.
In most cases, small garlic bulbs are caused by poor spacing, insufficient sunlight, shallow planting, compact soil, or improper feeding. The good news is that these mistakes are easy to fix once you know what to look for.
Below are the seven most common reasons garlic bulbs stay small, and exactly how to correct each one.
Mistake 1: Planting Cloves Too Close Together
Garlic needs room to expand underground. When cloves are planted too close together, they compete for nutrients, water, and root space.
Why It Causes Small Bulbs
Crowded plants cannot form large bulbs because their root systems overlap and compete.
How to Fix It
- Space cloves 4 to 6 inches apart
- Leave 8 to 12 inches between rows
- Avoid squeezing extra cloves into tight containers
Proper spacing alone can dramatically increase bulb size.
Mistake 2: Not Enough Sunlight
Garlic requires strong sunlight to produce large bulbs.
Why It Causes Small Bulbs
Bulb formation depends on healthy leaf growth, and leaves depend on sunlight for energy. In low-light conditions, plants may grow but fail to produce large bulbs.
How to Fix It
- Provide at least 6 to 8 hours of direct sunlight daily
- Avoid shaded planting areas
- For balconies, choose the brightest location available
Full sun equals fuller bulbs.
Mistake 3: Using Compact or Poor Soil
Garlic bulbs expand underground. If soil is compacted or heavy clay, bulbs cannot enlarge properly.
Why It Causes Small Bulbs
Tight soil restricts root development and bulb expansion.
How to Fix It
- Loosen soil 6 to 8 inches deep before planting
- Mix in compost to improve structure
- Avoid waterlogged areas
Loose, well-draining soil allows bulbs to reach full size.
Mistake 4: Planting Cloves That Are Too Small
Clove size directly affects bulb size.
Why It Causes Small Bulbs
Small cloves contain less stored energy, which limits growth potential.
How to Fix It
- Always plant the largest cloves from the bulb
- Save smaller inner cloves for cooking
- Select healthy, firm planting stock
Large cloves almost always produce larger bulbs.
Mistake 5: Overwatering
Garlic does not tolerate constantly wet soil.
Why It Causes Small Bulbs
Excess water can damage roots and reduce oxygen in the soil, slowing bulb formation.
How to Fix It
- Keep soil evenly moist but never soggy
- Reduce watering once bulbs begin forming
- Stop watering two weeks before harvest
Balanced watering improves bulb size and storage quality.
Mistake 6: Too Much Nitrogen Late in the Season
Nitrogen is helpful early, but harmful when bulbs begin forming.
Why It Causes Small Bulbs
Excess nitrogen late in the season pushes leaf growth instead of bulb growth.
How to Fix It
- Feed nitrogen early in the season only
- Stop heavy feeding once bulbing begins
- Focus on balanced soil rather than over-fertilizing
Timing fertilizer correctly makes a noticeable difference.
Mistake 7: Harvesting Too Early
Garlic needs time to fully mature.
Why It Causes Small Bulbs
If harvested before bulbs fully form, size and storage quality suffer.
How to Fix It
Harvest when:
- Lower leaves turn brown
- Upper leaves remain partly green
- About half the leaves are dry
This timing allows bulbs to reach maximum size without splitting.
Final Thoughts
Small garlic bulbs are rarely random. They are usually the result of spacing, sunlight, soil quality, watering habits, or fertilizer timing.
Fixing even one of these mistakes can improve next season’s harvest. Fixing all of them can transform your garlic yield completely.
Large bulbs are not luck. They are the result of proper growing conditions.
Frequently Asked Questions
Can small garlic bulbs grow bigger if left in the ground longer?
Not usually. Once leaves begin dying back naturally, bulb size is mostly set. Leaving them too long can cause splitting rather than growth.
Does mulch affect garlic bulb size?
Yes. Mulch helps regulate soil temperature and retain moisture, both of which support steady bulb development.
Does hardneck or softneck garlic produce bigger bulbs?
Hardneck garlic often produces larger individual cloves, but total bulb size depends more on growing conditions than variety alone.
Can container garlic produce large bulbs?
Yes, as long as the container is deep enough, properly spaced, and receives enough sunlight.
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