Here's How Spring Onions Differ From Scallions

Spring onions and scallions share a lot of similar traits, with long, slender green tops that transform into pearly white ends. Great for both raw and cooked recipes, their green parts are often used as a garnish. Finely chopped with a knife or snipped with a pair of scissors, chefs can generously sprinkle these green bits on top of a well-prepared omelet or any salad for an impressive final touch. The white shafts, on the other hand, offer more intense flavor and aroma, reaching their full potential when cooked and added to stir-fries or, for example, made into a French onion soup that will send your taste buds into a state of ecstasy.

But although they're often mistaken for one another, these two tasty members of the onion family are actually not as similar as they seem at first glance. The key difference, in fact, is whether or not they develop a bulb. While scallions don't form a real bulb, leading to them having a milder flavor, spring onions have a noticeable one, which tastes sweeter in comparison to regular onions.

Spring onions (Allium cepa) get their common name from their planting and harvesting cycle. Fast and easy to grow, all you need to do is sow the seedlings in late autumn, and you'll have them ready for harvest by early spring. They are also incredibly affordable, typically priced at around $2 per pound in the USA. These green-leaved alliums come from varieties which develop small bulbs at the base. This means that they are underdeveloped bulb onions which will grow into full-sized ones if left to mature. 

Because they are harvested before their bulbs fully develop, spring onions taste sweeter and milder than traditional onions. A fresh substitute for their aged counterparts, they are particularly delicious when added to sandwiches or salads. Their leaves, on the other hand, pack a slightly sharper taste, but provide a vibrant green touch to just about any dish.

Considered native to Central Asia, onions are now grown all across the globe and thrive in temperate regions where the balance of the four distinct seasons — spring, summer, fall, and winter — creates the perfect environmental conditions for their development. And as it turns out, their use in our diets dates back over five millennia, with our Bronze Age ancestors being the first to incorporate them into their recipes.

Scallions (Allium fistulosum), also called Welsh onions, are often referred to as spring onions over in the United Kingdom. But as their Latin name suggests, they're an entirely separate species. They get their name after Ascalonia caepa ("onion of Ascalon"), a term associated with Ascalon, a city now known as Ashkelon in Israel.

They have tubular green leaves that stem directly from their underdeveloped bulb. Except for the root at the base, every part of the scallion is entirely edible. Still, the white and green sections of the scallion have different purposes in cooking. Scallions are immediately recognizable for their strong aroma. This fascinating scent mostly stems from their white parts, while their green tops are a bit gentler on the nose. Available throughout the whole year, you can usually find a bunch of scallions for just over $1, particularly when they first appear at farmers' markets in springtime.

Though scallions are a great addition to a plate of steamed pork dumplings and can work wonders when grilled or added to sauces and salads, they're also exceptional medicinal plants. According to a 2023 study published in the "Journal of Applied Pharmaceutical Science," this is due to their sulfur and flavonoid content. Therefore, the next time you're not certain about whether to add scallions to your meal, just remember they can boost your immune system, ease abdominal pain, and even help combat arthritis. 

Even though spring onions and scallions taste nearly identical — they come from the same family after all — there are still several traits that set them apart. The most obvious difference? They're a completely different species. 

In terms of their appearance, scallions grow in bunches and have an almost unnoticeable bulb which may never even develop. In contrast, spring onions possess a spherical bulb that closely resembles a tiny onion. Flavor-wise, spring onion greens are richer and more flavorful than those of scallions. And unlike scallions, which have a spicier, sharper and more peppery flavor profile, they are much sweeter. 

The spring onions' natural sweetness makes them ideal for roasting whole. A simple drizzle of oil, a dash of salt, and a splash of lemon juice is all it takes to get them ready for the oven. Meanwhile, grilled or roasted scallions bring a smoky, savory kick to dips. Just stir them into sour cream and serve the mix with a bag of your favorite potato chips.