Garlic is a favorite crop for many home gardeners for many reasons. It’s easy to grow and it can grow quite well into the wintertime, depending on your climate. It’s rapidly become a quintessential part of any fall vegetable garden. Unlike most vegetable crops, this spicy allium is planted in the fall and harvested the following summer.
Under the frosty blanket of winter, garlic cloves work their magic and turn into big, flavorful bulbs for storage and use throughout the rest of the year. The exact planting time depends on your climate and the type of garlic you choose.
Let’s dig into exactly when you should plant garlic in the fall based on your USDA hardiness zone!
The Short Answer
For the most part, you should be planting garlic between September and November. In frigid northern zones 0 through 4, it can be planted throughout September. In zones 5 through 7, hardneck garlic is traditionally planted in October. Growers in zones 8 and 9 typically wait until October or November. Frost-free tropical growers in zones 10 through 11 often grow softneck garlic in only the coolest months of December through January, but can also plant hardneck garlic in October to November, particularly if they vernalize in advance.
The Long Answer
If you live in a mild climate, it is recommended to start planting 2-3 weeks before the expected first autumn frosts.
Garlic is one of the most low-maintenance crops you can grow, but it requires some planning to get the planting date right. This pungent onion-family crop requires a certain period of cold weather to develop bulbs.
The 4-8 weeks of cold temperatures (below 40°F) is called a vernalization period. The cold weather promotes the plants to start growing roots, go dormant for the winter, and return in the spring, ready to grow into plump bulbs.
In cool climates, the weather will do the work for you. But warm southern growers may need to trick their garlic into thinking it has faced the winter elements. Either way, if your garden gets a frost, it’s best to get the garlic bulbs in while the weather is still bearable.
However, you don’t want to plant garlic too early. Early planting results in poor growth and less likelihood of bulbing. The cloves may rot. To find a balance between planting too early or too late, remember these rules:
Plant 4-6 weeks before the ground starts to freeze, or right around the first light frost.
Plant 2-3 weeks before or after your estimated first fall frost. If the weather is unusually warm during fall, wait until a freeze.
If no frost, choose softneck varieties and refrigerate for 5-10 weeks before planting. Plant during the coldest season.
Use the USDA Plant Hardiness Zone Map to determine your growing zone, and then head to Farmer’s Almanac to calculate the estimated first frost date of the autumn. This will give you a good idea of the best window of opportunity for getting your garlic in the ground.
Planting Chart by Hardiness Zone
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Planting Time Based on Variety
It is recommended to plant hardneck garlic after the first fall frost to ensure that it gets 4-8 weeks of cold exposure.
While you can technically grow garlic anywhere in the U.S., certain types are better for certain regions. The two main categories are hardneck and softneck garlic. Their cultivation is similar, but their planting times and hardiness are unique:
Hardneck garlic is more cold hardy and best for northern climates. It requires the chilly winter (vernalization period) to create full bulbs. As the name implies, hardneck garlic has a stiff central stalk. They are the only kind of garlic that sends up buttery-delicious scapes (flower stalks) during the spring or summer. The cloves tend to be larger, easier to peel, and more complex in flavor.
Plant hardneck garlic right around the first fall frost to ensure that it gets a full 4-8 weeks of cold exposure below 40°F.
Softneck garlic is best for mild or warm climates. It only needs mild cold exposure (vernalization) to grow a bulb. This can be easily hacked with 5-10 weeks in a refrigerator before planting. Softneck varieties have a soft stalk for garlic braids. They have a longer storage life, smaller cloves, more wrappers, and mild to hot flavors.
In tropical climates, plant softneck garlic during the early winter after 5-10 weeks of refrigeration (not freezing).
Common Mistake: Planting Too Early
Planting too early can cause small bulbs and early shoots that will not withstand frost.
One of the biggest mistakes that beginner garlic growers make is planting too soon. This cold-hardy allium doesn’t just tolerate the cold, it needs it!
Think of garlic cloves (mistakenly called “seed garlic”) as plant storage capsules. Inside are all the starches, sugars, and genetics that the plant needs to grow before it can actually photosynthesize with its leaves.
Garlic is meant to establish some roots during the fall and then go dormant through the winter. In spring, it uses all of that cold-weather root growth to push up a sprout and start growing more cloves until it forms a bulb.
In the best case, planting too early will cause your garlic to have small bulbs (which are no fun to peel in the kitchen). However, in the worst-case scenario, planting too early can cause green shoots to go up too early.
When frosts come, the shoot dies, and the clove doesn’t have enough energy for spring. The clove could even desiccate (dry up), rot, or get eaten by rodents.
This is why spring-planted garlic can only ever become like a spring onion or scallion. It isn’t able to “bulb up” because it doesn’t get the cold exposure it needs. The same thing happens when southern or tropical growers try to plant during the fall: the weather is too hot, and it stunts the growth of the cloves, so they never develop bulbs.
Does Garlic Need Vernalization?
Garlic requires vernalization to reach its full potential.
Garlic plants need vernalization (a period of chilling) to trigger the plants to develop the big, spicy bulbs we crave. Without vernalization, you can end up with pathetic bulbs or cracked cloves with very low yields.
Unlike most garden veggies, garlic evolved in the frigid northern temperatures and actually requires cold to grow to its full potential.
Should You Refrigerate Before Planting?
If you are planting in zone 8 or warmer, consider refrigeration before planting.
If you live in a zone that freezes (zones 7 and colder), refrigeration of garlic is not necessary. However, if you garden in zone 8 or warmer, your garlic may benefit from refrigeration before planting.
In areas with warm winters, you need to fool your garlic into thinking that it’s way up north. Because softneck garlic requires less vernalization, southern growers typically opt for these varieties. But if you have the patience, hot-climate gardeners can also grow hardneck varieties. The ideal refrigeration times are:
- Softneck Garlic in Warm Climates: Refrigerate for 5-8 Weeks
- Hardneck Garlic in Warm Climates: Refrigerate for 10-12 Weeks
The warmer your winters, the longer you should refrigerate. For tropical gardeners, this means you will need to order your seed and get it in the fridge by August or September. When November rolls around, you can plant as the weather cools. A nice leaf or straw mulch can help keep the ground cool throughout the growth period.
Consider also how long your average cool weather is. For instance, many growers in zone 9 have the perfect conditions for growing garlic as long as it’s in the ground by early November; their cold season is usually December through February, and there will often be temperatures into the 20s. Zone 10 growers rarely see temperatures below the 30s, but have a similar timing for their chilly months. Zone 11 growers should definitely consider vernalizing!
Garlic should only be vernalized in the fridge at temperatures around 33-39°F. Do not freeze it! Instead, keep it dry in a paper bag to reduce the risk of rot.
Garlic is undoubtedly a slow-growing crop. It is best for patient gardeners who don’t mind leaving a garden bed to do its own thing for a long part of the year. Thankfully, if you prepare and plant garlic at the right time, it does all the hard work for you.
All those months of growth require little help from you until it’s time to harvest in the summer! Aside from some summer irrigation and a generous layer of mulch, garlic can grow in many conditions. It can grow in the shade and handle even some of the colder winter months!