Walla Walla Onion Plants (Heirloom, Long Day)

Walla Walla is the legendary sweet onion of the Pacific Northwest, tracing its roots to 1900 when French soldier Peter Pieri brought seeds from the Mediterranean island of Corsica to the Walla Walla Valley—where generations of careful selection by Italian immigrant farmers like the Arbini and Locati families transformed it into the ultra-mild, jumbo sensation we know today.

This long-day variety thrives in cool northern summers, producing flattened golden bulbs with ultra-juicy, translucent white flesh that's famously sweet enough to eat raw like an apple, earning it the title of Washington's official state vegetable in 2007 after a spirited student-led campaign. Each bundle contains approximately 75 healthy, premium, non-GMO plants grown with natural and regenerative practices. Use fresh; not a storage onion.

Key Details at a Glance

• Day length: Long-Day (best in zones 3–6)
• Days to maturity: 90–100 from transplant
• Mature bulb size: 4–6+ inches
• Storage life: 1–2 months (best eaten fresh)
• Bundle size: Approximately 75 bare-root plants

Why Grow Walla Walla?

• Sweetest onion available – Virtually no bite; kid-approved raw, thanks to low-sulfur valley soil.
• Northwest icon – Official vegetable of Washington state; a true heirloom with Corsican heritage.
• Early harvest – Ready before most long-day types; hand-harvest for delicate texture.
• Grilling star – Caramelizes beautifully; high water content yields deep, warm flavors when cooked.

Growing Tips Direct-transplant as soon as soil can be worked in early spring (soil ≥40°F). Space 4–6″ apart in rows 12–18″ apart. Provide full sun, consistent moisture (1″ weekly), and occasional nitrogen boosts. Mulch to retain moisture and suppress weeds. Harvest when 50–70% of tops yellow and fall over; cure in a dry, airy spot for 2–3 weeks.

Standard Information

• Plant type: Bulbing onion (Allium cepa)
• Sun: Full sun (6–8+ hours)
• Soil: Well-drained, fertile loam; pH 6.0–7.0
• Water: Consistent, especially during bulb formation
• Hardiness zones: 3–9 (bulbs form best in long-day regions)

Origin & Quality All plants are grown and shipped as bare-root, dormant starts in biodegradable wrap from Sunbelt Transplants, a trusted leader in premium onion transplants based in the heart of U.S. onion country.

Disclaimer Although these onions are grown by farms that are certified organic, we are not allowed to say it is Certified due to the rule 7 CFR § 205.2. The Farm On Central is in the process of becoming a Certified Handler for the 2026 season. All product provided for the 2026 season will be certified.