Onion Classification: Types and Varieties

There are a number of ways in which Onions are grouped. Grouping onions by taste is one way . You have only Sweet or Pungent using this method.

The pungent or strong-flavored varieties and the milder ones. Milder varieties include Slicing varieties that we use for onion rings and sandwiches, like ‘Sweet Spanish’, and big red onions.

Grouping onions by storage qualities is another method. The most popular storage onions are pungent strong flavored yellow ones .

Commercial growers like these onions because they store them for long periods of time and can be shipped greater distances. The milder Bermuda and Spanish onions can’t be stored for very long.

Marketing and Culinary Classifications

For marketing and culinary purposes, onions are generally categorized into the following:

White Onions

Glossy white appearance. One of the more pungent onions. Use raw on burgers, sandwiches, salsa and similar dishes if you like warm, but real tasty onions. Otherwise, they can be used in any recipe that calls for cooked onions.

Yellow Onions

Golden color with relatively strong flavor. May be used cooked or raw, depending on your taste for a somewhat pungent onion. Long, slow sauteing at very low heat brings out sweet, mellow flavors.

Red Onions

Purplish rather than red, they are relatively mild. Appealing in salads or sauteed in stir fries. Also good for many other recipes. Adding a bit of vinegar, wine or lemon juice helps keep color from fading or turning purplish-blue. You’ll often find red onions in salads at restaurants.


This is not a true onion, it is a small relative of the onion with dry, coppery skin. The flavor combines onions and garlic. Hot when raw, but cooks to a delicate flavor.


This is a variety of onions that is harvested before the bulb has formed. Mild flavor. Green onions have tiny white bulbs at the bottom while scallions are younger and have straight white sides at the root end.


In the scallion family. It looks like a large, fat scallion with a white root and dark green, overlapping leaves. Only the root is used. Careful trimming and cleaning are necessary because dirt can accumulate in leaves.

Leeks are not true Onions as per many “experts’, but in my book if it looks like a duck, quacks like a duck and tastes like a duck – it’s a duck. Or an onion as the case may be.

Egyptian Walking Onions

These are an unusual type of onion. They are believed to be a hybrid mix of Welsh and common onions. They produce bulbs from a stalk in clusters as opposed to standard onions which produce subterranean bulbs.

Read more about Egyptian walking onions.

Grouping Onions For Growers’ Purposes

Onions are generally categorized by how much daylight they need to form a bulb. Onions form a top first , later, depending on the type of onion variety and daylight hours, they begin to form the bulb / Onion.

Onions are grouped by day length

“Long-day” onions stop forming tops and begin to form the bulbs when the daylight hours or “day-length” reaches 14 to 16 hours.

“Short-day” onion varieties will start forming bulbs earlier in the season at 10 to 12 hours of daylight.

Long-day onion varieties generally fare better in northern regions , while “short-day” onion varieties will do better in southern states.

Short Day Varieties of Onions

Baby Onions also known as Pearl Onions are generally a variety of tree onion, often used for pickling or as cocktail onions. They are used in many different recipes. They have a sweet, mild flavor and attractive, petite size.

White Bermuda, Barletta (also called White Pearl), White Mexican are common short-day varieties that are used in Northern areas to produce Pearl Onions , cocktail onions, baby onions.

Candy Hybrid – relatively easy to grow. Jumbo size onions are incredibly sweet and mild.

Red Burgundy Onions 3-4″ bulbs, covered in dark red skin with white flesh with red rings. Short shelf life makes it good for the backyard gardeners who don’t have the need to store them.

Long Day Varieties of Onions

Yellow Sweet Spanish probably the most common onion you’ll see in the grocery store. The mildly sharp flavor does not overpower but melds well in all recipes.

Walla Walla Onion Plant is so-called because it hails from an area of Washington State known as Walla Walla. Southern growers will fare better with a hybrid simile known as Candy Hybrid

The Copra Onion Plant is the best long-storage onion for the northern parts of the country. Its sweet flavor is slightly pungent

This list is far from extensive, it is simply some of the more popular varieties. There are a myriad of varieties to suit varying requirements, scan through the online nurseries for further ideas.