Grocery Guides

Onions – All You Need to Know | Instacart Guide to Fresh Produce

What are onions?

Among the most versatile types of fresh produce, onions are of the genus Allium. As edible bulbs, onions come in various shapes, sizes, colors, and flavor profiles.

Onions can be served raw or cooked and may be used for a wide range of recipes, including in:

  • Soups
  • Salads
  • Sauces
  • Hamburgers and hot dogs
  • Omelets
  • Tacos

Among the many types of onions are:

  • Yellow onions
  • White onions
  • Red onions
  • Green onions
  • Leeks
  • Shallots (often categorized as a separate type of produce)

Home chefs know that preparing onions often results in their eyes tearing. That is because they contain a chemical known as syn-Propanethial-S-oxide. That irritant stimulates the eyes’ lachrymal glands, which releases tears. However, many methods have been shown to reduce the “crying factor” when peeling or chopping onions. Among these hacks are using a sharp knife, chilling the onion in advance, and running the oven fan while preparing onions.

Onions also have a wide range of other uses beyond cooking and eating.

Where did onions originate from?

People have been consuming onions for more than 5,000 years, but historians disagree about their first origins. Some believe that they first grew in central Asia, but others trace their roots to Iran and West Pakistan. Paintings of onions even appear inside the pyramids!

Pilgrims brought onions with them when they came to America, where they were already being grown and consumed by Native Americans.

Because they are easy to grow and can be raised in a wide range of soils and climates, onions were among the earliest cultivated crops.

What are the benefits of eating onions?

Onions contain a high level of quercetin. They also contain more than 25 different varieties of flavonoid antioxidants.

Onions are also a great source of:

  • Vitamins C and B6
  • Thiamin
  • Potassium
  • Calcium
  • Manganese
  • Copper
  • Zinc
  • Iron
  • Selenium

Raw onions are slightly healthier than cooked onions because they contain more sulfur compounds.

How are onions grown?

Onion plants start to grow when the weather is cool and form bulbs as the weather starts to warm. They are planted 4–6 weeks before the last frost.

Usually planted in the spring or fall, onions grow in rows or raised beds. They prefer soil that’s fertile and located in full sunlight. The soil must be kept wet, but too much water will cause the onion plants to rot.

When are onions in season?

Onion harvesting usually begins in the middle of summer. But they can be found year-round and are also available in various shelf-stable forms like onion powder and dried onion flakes.

Most economical when bought in-season, onions will keep for quite a while, so people often buy them in bulk to keep them on hand for recipes. Like other root vegetables, they add dimension and a hearty taste to a wide range of meals.

What should I look for when buying onions?

Because onions come in many colors and varieties, decide between a sweeter flavor or one that has more bite. First, decide on the type of onion or choose a few different varieties. Whatever type you select, it should feel heavy in your hand and firm to the touch. The skin should be dry and papery.

Instacart offers convenient same-day delivery or pick-up for onions! Once onions are added to your cart, use the “Instructions” option to give specific preferences or directions on choosing the best products. Shop for onions.

How to store onions

Before onions are peeled, they should be stored in a cool, dry, dark, and well-ventilated space like a pantry, basement, or garage. When stored this way in temperatures between 45 and 55°F, whole onions will last 2 to 3 months.

The best way to store onions is to provide sufficient ventilation. This can be achieved by placing them in a basket, loosely covered paper bag, or mesh bag. Do not store onions in plastic bags because they limit airflow.

  • When onions are chopped or sliced, they must be stored in airtight containers in the refrigerator, where they will last up to 10 days.
  • Cooked onions may also be refrigerated in airtight containers. They will last up to 4 days that way.
  • Raw onions may also be peeled and chopped or sliced for freezer storage. They can be stored in tightly wrapped aluminum foil or plastic wrap or placed in an airtight container. That will extend their life up to 8 months.
  • For maximum longevity, freeze cooked onions and store them for up to a year in an airtight container or freezer bag.

How to tell if onions are bad

Mold is the most obvious sign that onions are turning bad. Before that, they may develop dark or mushy spots.

Also, avoid onions that have started sprouting, are discolored, or have an unpleasant smell. Onions normally have a strong odor, but if the scent is unpleasant or putrid, the onion will most likely not taste good.

What can I substitute for onions?

Purists will say that if fresh onions aren’t available, substitute onion flakes or onion powder. Home chefs should keep these ingredients on hand throughout the year.

But other alternatives include scallions, leeks, chives, and garlic. Celery and carrots can also be used. They will add crunch and flavor, but they will have a radically different taste.

Where can I find onions near me?

For the greatest range of onions all year round, order from Instacart. Enjoy the convenience of delivery within 2 hours or pick-up at the local grocery shop! Especially when buying onions in bulk, shoppers find the convenience and choice to be very helpful. More time can be spent experimenting with recipes and less time running errands.



Instacart is the leading grocery technology company in North America, partnering with more than 1,400 national, regional, and local retail banners to deliver from more than 80,000 stores across more than 14,000 cities in North America. To read more Instacart posts, you can browse the company blog or search by keyword using the search bar at the top of the page.

Most Recent in Grocery Guides

15 Tasty Ice Cream Alternatives: Yogurt, Shaved Ice & More

Grocery Guides

15 Tasty Ice Cream Alternatives: Yogurt, Shaved Ice & More

Ice cream has been a beloved treat for generations. With its rich flavors and smooth texture, it’s no wonder people choose ice cream when looking for dessert. However, as dietary restrictions and health consciousness evolve,…...

Apr 10, 2024
When Is Artichoke Season? [Recipes + Guide]

Grocery Guides

When Is Artichoke Season? [Recipes + Guide]

Quick Answer When is artichoke season? In North America, artichoke season is from March to May, with smaller batches in October. Artichokes are a unique and versatile vegetable known for its tender heart and delicate…...

Mar 6, 2024
Brown Eggs vs. White Eggs: How Are They Different?

Grocery Guides

Brown Eggs vs. White Eggs: How Are They Different?

Eggs are an essential ingredient in many sweet and savory recipes. The possibilities are endless when it comes to using these protein-packed powerhouses — you can scramble, fry, boil or poach eggs, or you can…...

Feb 24, 2024

Free delivery or pickup on your first order of $35 or more. Sign up now! Terms apply.