How to grow larger garlic bulbs – every time

Everyone should grow garlic. It is easy and low maintenance, and when you get it right, you are rewarded with garlic to use in your cooking.

But as garlic is a slow grower, you will not know how big your garlic bulbs will be until harvest. And for most types of garlic, this will take 6-8 months.

Today I list 11 easy-to-follow tips that will ensure you harvest good-sized garlic bulbs.

I have grown garlic in containers for many years, but it was not until I got these 11 tips under control that I started to harvest garlic bulbs that were as big as the ones I could buy at the supermarket.

And as for taste and flavor profile, store-bought garlic is nowhere near as tasty as the garlic you harvest in your garden.

11 tips for growing larger garlic bulbs

1. Make sure you choose a suitable variety of garlic

Choose a garlic variety ideal for your climate to harvest large bulbs. 

Before planting, you must decide whether to grow hardneck garlic or softneck garlic. 

The table below lists the main differences between hardneck and softneck garlic:

You can choose either or both. But be aware that hardneck garlic must be exposed to freezing temperatures to come alive and start growing. 

There are techniques where you place bulbs in the fridge crisper to mimic winter before planting, but if you live in a warm climate, choose softneck garlic.

Planting hardneck garlic in march will result in small garlic bulbs when it is time to harvest.

2. Plant garlic cloves in the fall

Garlic is a slow grower and wants to lie semi-dormant in the ground over winter. But at the same time. You do not want to plant too early.

My best tip is to plant your cloves 2-3 weeks before the first expected frost.

Planting in the fall will allow the garlic cloves to establish roots before winter, which helps them grow large and more flavorful in the spring.

Choose a location with full sun and use fertile well-draining soil (pH 6.0 to 7.0).

3. Prepare the soil for your garlic plants

Garlic wants rich, fertile soil that drains well. Use slow-release fertilizers and compost to give your garlic bulbs the nutrients needed to grow large and robust.

You want the soil to be loosely structured. Hard soil needs to be improved for the best results. 

Solid amendments like coarse sand, perlite, and vermiculite can all be used to make your soil softer to promote soil retention and larger bulbs. 

One tip is to dig around and loosen the soil to a depth of about 20 centimeters / 8 inches to allow the bulb’s roots to grow freely.

4. Get the spacing right

Common gardening wisdom says to plant garlic cloves 6-8 inches apart. And I live by this.

Garlic plants do not like competition; if you want to grow larger bulbs, you need to give the plant space to grow. 

On the other hand, planting cloves too far apart are simply a waste of valuable growing space.

5. Get the planting depth right

Plant your cloves 7 cm (3 inches) deep. Some guides recommend a depth of 2-7 centimeters/1-3 inches, but I garden in a climate with snow and freezing temperatures in winter, and 7 cm (3 inches) has worked great over the years.

If cloves are planted too deep, the plant will unnecessarily have to spend time and energy to break through and sprout. 

But do not plant the cloves too shallowly. You do not want to risk cloves freezing.

6. Plant the cloves pointed end up

Always plant garlic cloves with the pointed end facing up. 

But, it is easy to make mistakes when planting rows after rows of cloves.

Cloves planted upside down will unnecessarily use energy to turn around and sprout. You want all energy to be used to develop large bulbs.

7. Water your garlic regularly

Garlic wants a consistent level of moisture to grow large bulbs. 

Water regularly, especially during hot times of the year, to ensure that your soil stays evenly moist. 

But do not over-water. Watering too much can lead to root rot and attract pests and diseases. Also, water your garlic plants at the base. Watering from above will risk getting leaves wet and exposing the plants to fungal infections.

8. Mulch your garden bed to retain moisture

Mulching your garden beds will help the soil retain moisture and prevent weeds from growing. 

Add a 1-2 inch layer of straw, hay, or wood chips around the base of your garlic plants. Here more is better. 

9. Fertilize your plants regularly

Garlic plants are heavy feeders and benefit from regular fertilization, especially during the growing season. 

But go easy with the nitrogen as it primarily promotes leaf growth, and you want the energy to go into developing larger bulbs.

Compost is ideal. If not available, use a balanced fertilizer with an NPK 10-10-10 formula. 

Another tip is regularly improving your soil with additional nutrients by adding compost,  grass clippings, or well-rotted manure.

10. Protect from pests

My garlic plants have never had problems with pests, but it is good to be aware of Garlic Bloat Nematodes [1].

These nematodes attack garlic but also onions, chives, and leeks. Stunted growth, wilting, and yellowing leaves can be signs of nematode infection. Nematode infection will result in shrunken, soft, and no-good-to-use garlic bulbs.

Nematodes can be introduced into your garden from store-bought garlic bulbs. This is one of the main reasons why you should always buy seed garlic from a reputable source. Do not risk it. It is not worth it. Getting rid of a nematode infection is, from what I have read, no easy task and can involve replacing your soil.

Other pests I have read about include aphids, slugs, and thrips. But to be honest, I am skeptical.

Garlic plants are vigorous growers; in my garden, they are used as beneficial companion plants to keep pests and unwanted insects at bay.

11. Cut scapes to promote bulb growth

Cutting garlic scapes or not, that is the question.

I do not cut the garlic scrapes on my hardneck garlic plants. I harvest them and use them in cooking. They freeze well and are great to have at hand when the supply of homegrown garlic starts to run short.

But yes, do cut the scapes as soon as they form if your primary objective is to grow larger bulbs. The scapes consume energy as they grow, which could help your plants develop larger bulbs.

Bonus tip! Small cloves equal small bulbs

This last tip is more of an observation than a pure fact. 

But when preparing cloves for planting, you will see that not all cloves are the same size. And from my experience, the larger cloves produce more vigorous plants and larger bulbs. 

One way to test my findings is to divide your cloves into two piles—one for larger cloves and the other for smaller cloves. Now keep a record of where you plant them, and then please get back to me with our findings. 

I feel very confident. But I would love to hear from you.

Helpful resources:

[1] https://ag.umass.edu/vegetable/fact-sheets/garlic-bloat-nematode