Onions are a versatile vegetable essential to cuisines around the world. Their rich, savory flavor enlivens everything from soups and salads to main dishes. While fresh onions can be found in supermarkets all year round they are actually a seasonal crop.
Understanding onion seasonality helps you select the best onions for your needs It also allows you to enjoy peak flavor onions when they are at their freshest
The Peak Onion Growing Season
The main onion growing season lasts from spring through late summer. Peak availability is typically:
- Yellow, white, and red onions: early June through August
- Sweet onions: May through July
- Green (spring) onions: March through June
During these months, most onions in stores are freshly harvested and not in long term storage. Their quality is at its best in terms of flavor, texture, and nutrient content.
Spring and Summer Onions
Spring and summer onions are harvested before fully maturing. Characteristics include:
- Thin, flaky, light-colored outer skin
- Higher water content
- Mild or sweet flavor
- Shorter shelf life
These onions are best used fresh in salads, salsas, sandwiches, and light cooking. Frequent replenishment from local farms keeps supplies plentiful in summer.
Sweet Onions
Sweet onion varieties like Vidalias and Walla Wallas are harvested in late spring and early summer. Their sugar content is higher before fully maturing, giving them a mild, sweet taste perfect for eating raw. They also have a short shelf life.
Onion Availability Year-Round
Onions harvested at full maturity in late summer and fall are suitable for long term cold storage. This allows them to be sold fresh year-round. Characteristics include:
- Thicker, darker outer skin with many layers
- Lower moisture content
- Long shelf life of up to 8 months
- Sharp, pungent flavor
Cold storage onions are great for hearty cooked dishes and can be found fresh in markets every month. Additional industry practices ensuring year-round onion supplies include:
- Imported onions from South America available November through March
- Onions grown in controlled greenhouse environments
- Frozen and dehydrated onion products
Onion Varieties Through the Seasons
The timing of onion varieties reaching peak ripeness varies:
-
Spring: Green onions, Vidalia sweet onions
-
Early summer: Yellow granex, white onions, Maui sweet onions
-
Midsummer: Red onions, yellow Spanish onions, Walla Walla and Texas sweet onions
-
Late summer/fall: Sturdy storage varieties like yellow globe and red Italian types
This succession of harvests makes fresh onions available in abundance during warmer months. Different onion varieties also store better at various points in the season.
How Storage Affects Onion Quality and Flavor
Onions stored for months undergo gradual physiological changes:
-
The outer skin layers become dry and papery.
-
Sugars converting to starches makes them lose sweetness.
-
Sharp flavors intensify as pungent compounds increase.
-
They begin re-sprouting by early spring.
While still usable, older cold-stored onions lack the sweetness and moisture content of summer fresh onions. Their texture also becomes softer.
Tips for Choosing the Best Onions
Keep onion seasonality and storage life in mind when selecting onions:
-
For raw uses, choose sweeter varieties in spring and summer. Avoid sprouting onions.
-
For long cooking, pick storage onions in fall through winter.
-
In spring, inspect skins and avoid onions with green sprouts.
-
Heaviness indicates moisture content; lighter onions are older.
-
Loose, shaggy skins signal freshness in summer and fall.
-
Solid, papery skins in winter mean longer storage life.
-
Buy onions with dry, intact outer layers without spots or blemishes.
Growing Onions for Year-Round Harvest
With planning, you can enjoy fresh onions from your garden almost any time:
-
Spring: Sow seeds of hardy green onion varieties 4-6 weeks before your last frost.
-
Summer: Plant onion sets or transplants of bulbing varieties in early spring. Choose sweet types for fresh summer use.
-
Fall: Sow seeds of yellow, white and red storage varieties 8-12 weeks before your first fall frost.
-
Winter: Harvest mature bulbs in late summer and store properly in a cool, dry spot. Check regularly and use sprouting bulbs first.
With a succession of plantings, you can have a year-round onion harvest. Cure and store only your best bulbs for winter and spring use.
How to Store Onions for Long-Lasting Freshness
Proper curing and storage lets you keep fresh onions up to 8 months. Here’s how:
-
Cure bulbs thoroughly in a warm, dry spot immediately after harvest. Let the necks shrivel and outer skins form multiple layers.
-
Store cured bulbs in mesh sacks or shallow crates at 32°F to 40°F with low humidity and good air circulation.
-
Inspect regularly and remove any bulbs starting to sprout or show signs of rot. Use them first since they won’t store as long.
-
Keep different varieties separate if storing for several months, since they have varied dormancy periods.
-
Move to refrigerator in late winter to inhibit premature sprouting as dormancy breaks.
With attentive storage methods, you can enjoy fresh onion flavor all the way from one summer to the next!
Enjoying Onions Year-Round
Here are some tips for making the most of onions each season:
-
Sauté sweet spring onions or green onions for a flavor boost to pastas, pizza, omelets and more.
-
Roast fresh summer onions with seasonal veggies; use their bright flavor to top grilled meat or fish.
-
Caramelize fall storage onions slowly to bring out rich, complex flavors for French onion soup, onion jam, etc.
-
Bake or grill thick slices of winter storage onions as flavorful onion rings or side dishes with roasts.
-
Use sprouting spring onions quickly in soups, stocks, and stir fries. Their shoots are also edible!
Understanding the seasonal differences and uses for onions allows you to get the best results from recipes. With proper storage methods, you can enjoy their versatile flavor all year long!
:max_bytes(150000):strip_icc()/red-onions-7110784-hero-79e37549208f4b21a95481bcb7725cb1.jpg)
Seasonal Differences of Onions
Yes. Onions are seasonal! Based on when they are harvested, onions grown in the U. S. can be divided into two categories. Read about the Seasons, Colors, Flavors, and Sizes of Onions….
- Available in yellow, red, and white from March through August
- Can be identified by their thin, lighter-colored skin
- Usually have more water in them, which makes them less stable and more likely to get bruised.
- Range in flavor from sweet to mild
- It goes well with salads, sandwiches, and fresh, lightly cooked or grilled foods.
- In this group are a lot of specialty sweet onions that are sold under a certain brand name or label.
- Please note that these onions are available at other times of the year, both in the United States and other countries.
- Available August through May in yellow, red, and white
- Easy to spot because their skin is thick and dark in many layers.
- Commonly lower in water content, they have a longer shelf-life
- Range in flavor from mild to pungent
- Best for savory dishes that need more flavor or more time to cook
Bulb onions can be yellow, red, or white. Around 87% of the crop is used to grow yellow onions, 8% is used to grow red onions, and 5% is used to grow white onions.
Yellow Onions
Yellow Onions are full-flavored and are a reliable standby for cooking almost anything. Yellow onions turn a rich, dark brown when cooked and give French Onion Soup its tangy sweet flavor.
Because of their beautiful color, red onions can be used in a lot of fresh ways or grilled, charbroiled, or roasted.
White onions are the traditional onion for Mexican food and are often used in prepared salads and white sauces. They have a golden color and sweet flavor when sautéed.
Time To Start Onions From Seed – Everything You Need To Know – Long Day Short Day – Sets vs Seeds
FAQ
What is the season for onions?
What month is best to buy onions?
Do onions go out of season?
Are onions in season all year?
Are onions seasonal?
Yes. Onions are seasonal! Based on when they are harvested, onions grown in the U.S. can be divided into two categories. Read about the Seasons, Colors, Flavors, and Sizes of Onions… Note: Some domestic and all imported onions with these traits are offered other times of the year. Bulb onions can be yellow, red, or white.
How can one consume onions?
In the raw version, we consume a greater amount of potassium, calcium and phosphorus. We can think of creative ways to use onions, such as: salt seasoned with onions, pickled, in salads and as an ingredient in guacamole. Consumption of sautéed onions is common in sauces, as an accompaniment to meats, quiches and other dishes. An interesting way is to use it with rice at the time of cooking, to give a special flavor to the main dish. Fried, it can be part of the main course or an appetizer, like the famous onion rings. However, attention: the use of flour for breading and oil for dipping contribute to the increase of cholesterol.
When are onions ready to harvest?
Onions are ready to harvest when the top part of the plant has dried out, browned, and fallen over. Harvest by pulling up directly from the foliage. Curing onions allows them to last for months during winter. The dried, cured skin helps preserve the onion. Compassionate Eye Foundation/Natasha Alipour Faridani / Getty Images
When should I plant onions?
Plant onions sets as soon as the garden can be worked. Rich soil, consistent moisture and cool temperatures help bulb development. It’s best to create hills for onions that are to be used for green onions but do not hill those to be used for bulbs.
When is the best time to buy onion?
Sweet, mild, or spicy, and yellow, red, or white, and from super colossal to pearl – onion grown in the U.S. are available year-round. March is the time of year when these differences are most prominent as onion supplies transition from Fall/Winter harvested varieties to Spring/Summer varieties.
What is the difference between fall & winter Onions?
Notice in the image above, how the skin color varies. On the left, the onion in front and the ones behind it are Fall/Winter types. The other two in front, towards the right are Spring/Summer varieties. Another difference is their shape. Most Fall/Winter types are globe shaped. Many, although not all, Spring/Summer types are flatter in shape.