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All About Walla Walla Onions

Walla Walla Onions have a reputation for being one of the sweetest and most distinct-tasting onion varieties available. Known for their mild and sweet flavor profile, these onions are a staple in various culinary creations.

The unique taste of Walla Walla Onions is attributed to generations of selective cultivation and the perfect combination of climate and volcanic soil low in sulphur compounds, which are responsible for the harsh bite in ordinary onions.

This flavorful and highly sought-after onion has its roots in the Walla Walla Valley, where its exclusive growth and production contribute to its unique character.

Closeup of fresh white walla walla sweet onion bulbs with green stems for sale at an outdoor farmers' market.

Walla Walla Onion History

The story of the Walla Walla Sweet Onion began over a century ago on the Island of Corsica, off the west coast of Italy. A French soldier named Peter Pieri discovered a sweet onion seed there and decided to bring it to the Walla Walla Valley in the late 1800s.

In 1900, the first harvest of Walla Walla onions took place in the valley. The early growth of this distinctive onion can be attributed to the Italian settlers who arrived in the region during the 19th century.

The Walla Walla Sweet Onion eventually became an essential part of the Italian-American community and a symbol of their identity.

In 2007, the Walla Walla Sweet Onion was officially declared the state vegetable of Washington. Today, it is enjoyed for its uniquely sweet flavor and versatility in both traditional and contemporary recipes.

The Walla Walla Sweet Onion continues to be a point of pride for the local community and a testament to the rich history and cultural diversity of the Walla Walla Valley.


Characteristics of Walla Walla Onions

Onions on display at the fair

Size and Shape

Walla Walla onions are known to grow in medium to large sizes, with globular shapes and rounded ends. While many other onion varieties can have a flatter or more oblong shape, the Walla Walla onion is characterized by its distinct roundness.

Sweetness and Mild Flavor

What sets Walla Walla onions apart from other onions is their sweet and mild flavor. As a type of sweet onion, they are less pungent and have a more pleasant taste when compared to other onion varieties.

This makes them an ideal choice for eating raw in salads and sandwiches, or for caramelizing to bring out their natural sweetness.

Low Sulfur Content

One reason Walla Walla onions have a milder flavor is their relatively low sulfur content. Sulfur compounds are responsible for the pungent taste and tear-inducing effect of other onions.

The low sulfur content in Walla Walla onions not only contributes to their mild flavor but also makes them a more comfortable choice when preparing and cooking.


Growing Walla Walla Onions

Sweet White Onions Growing In The Garden

Ideal Climate and Region

Walla Walla onions thrive in the Pacific Northwest, specifically in the Walla Walla Valley of Washington State. This growing region provides a favorable climate with mild temperatures and adequate rainfall, perfect for cultivating these sweet onions.

Walla Walla onions require a well-drained soil and prefer a location with full sun exposure.

Planting and Harvesting

You can choose between planting onion seeds or using Walla Walla onion starts for your garden. Onion starts are typically grown in the early spring and transplanted into the garden later.

Plant Walla Walla onions in rows, spacing them about four to six inches apart. Ensure that the planting area provides adequate drainage to prevent waterlogged roots.

Keep the soil consistently moist but not waterlogged by watering regularly, especially during dry spells.

Apply a balanced fertilizer every few weeks to encourage growth and bulb development.

Walla Walla onions can be harvested when the tops have fallen over and become dry, usually around late summer or early fall.

By following these guidelines and understanding the specific climate and regional requirements for Walla Walla onions, you can enjoy the delicious, sweet flavor of this unique onion variety in your home garden.


Cooking With Walla Walla Onions

Walla Walla onions, known for their distinctively sweet taste, are a perfect ingredient to enhance numerous dishes. Harvested during the summer season, there are various ways to enjoy these fresh, juicy gems.

Raw Onion Uses

  • Salads: Adding raw Walla Walla onions to your mixed greens or spinach salad will give a mild, sweet crunch without the pungent taste of regular onions.
  • Sandwiches: Layering thinly sliced onions on your sandwich, particularly with cold cuts or cheddar cheese, adds a delightful flavor.
  • Salsas: Chop up Walla Walla onions into small chunks and incorporate them into salsas, perfect for summer gatherings.

Grilling and Baking

  • Grilled Sweet Onions: Peel and cut Walla Walla onions into thick slices, coat with olive oil, and skewer for grilling. Sprinkle with salt or drizzle with sherry for a tasty side dish.
  • Roasting: Preheat the oven to 425°F, and roast whole Walla Walla onions to magnify their sweetness and add a caramelized touch.

Freezing and Preserving

Walla Walla onions have a limited shelf life. To make them last longer, consider freezing and preserving them.

  • Freezing: Chop the onions into slices or chunks and lay them flat on a parchment-lined baking sheet. Place in the freezer until frozen, then transfer to a sealed freezer-safe container. Onions can be used for cooking directly from frozen.
  • Preserving: You can pickle Walla Walla onions for longer-lasting usage. Boil onion rings and pepper rings, pack them into sterilized canning jars with a bay leaf, and pour the hot pickling liquid over them. Allow them to cool before sealing the jars.

Where to Buy Walla Walla Onions

Organic sweet onion in rubber bands on display at farmer market stand in Washington, America. Blurry black food crate in background. Organic fresh Walla Walla sweets onion variety.

To start your walla walla onion cultivation journey these walla walla onion seeds are perfect for you.


Frequently Asked Questions

What are the best uses for Walla Walla onions in cooking?

Walla Walla onions are versatile and can be used in various dishes. They are particularly well-suited for caramelizing, grilling, and using raw in salads or sandwiches. Their mild, sweet flavor adds depth to soups, stews, and casseroles.

What sets Walla Walla onions apart from other onions?

Walla Walla onions are known for their large size, mild flavor, and sweet taste compared to other onion varieties. Their relatively high water content results in a tender texture when cooked. Additionally, they are less pungent and have a shorter shelf life than common onions.

Are Walla Walla onions available outside of the Pacific Northwest?

Walla Wallas are primarily grown in the Pacific Northwest, but they may be found in select markets and specialty grocery stores nationwide during their peak season. Availability may vary depending on geographic location and shipping logistics.


Wrapping up Walla Walla Onions

Growing these onions requires careful attention to planting and harvesting timelines, as well as specific growing conditions. If you’re interested in cultivating these onions, it’s essential to understand when and how to plant them to ensure a successful and bountiful harvest.

With proper care and attention, you can enjoy the unmatched flavor and juiciness of Walla Walla Sweet Onions in your own home and discover why they have become such a beloved staple in many kitchens. For more about onion cultivation and varieties, check out our onion hub page.