There’s something about the way the golden sun hits the garden in late spring that calls us back to the soil. And when it does, we’re usually out there sowing Walla Walla onion seeds. If you’ve ever tasted one fresh from the ground, you’ll know exactly why.

They’re sweet, tender, and just plain satisfying to grow. But getting them there from seed? That takes some know-how. Lucky for you, we’ve done this more times than we can count—and now, we're laying out exactly how we make it happen.

Key Takeaways

• Walla Walla onions have that trademark sweet flavor that makes them a favorite in home gardens.
• You’ll get a step-by-step breakdown of how we grow them from seed to harvest.
• We’ll walk you through soil prep, seed starting, transplanting, and proper care throughout the season.
• Whether you’ve got calloused hands from years in the garden or you're just getting dirt under your nails, this guide is designed with you in mind.
• We cover everything from climate nuances to spacing specifics—nothing skipped.

Knowing What Makes Walla Walla Onions Tick

If there’s one thing we’ve learned, it’s that not all onions are created equal. Walla Walla onions, for instance, thrive under specific conditions. They’re what’s called a long-day variety, which means they demand at least 14 hours of sunlight to develop those big, sugary bulbs.

They do especially well in areas with cooler climates—think places with long, mild summer days and crisp evenings. We’ve had the best results in regions similar to the Pacific Northwest. Not every spot will be perfect, but if your summers are gentle and your soil drains like a dream, you’re off to a solid start.

Understanding the Growing Conditions They Crave

These onions like their environment steady and unhurried. They prefer cool, consistent temps, and they’re picky about moisture—too little and they stall out, too much and you risk rot. What they want is a breathable, nutrient-rich home that holds moisture just right without turning soggy.

If your region swings from bone-dry to soaking wet in a single week, you’ll need to stay on your toes. Some light mulching and smart watering go a long way. It’s not impossible, just a little more involved.

Walla Walla Onion Traits That Set Them Apart

Honestly, these onions are real charmers. They’re known for a delicate sweetness with very little bite, and the texture? Juicy, almost crisp. Slice one into a sandwich or dice it into a fresh salsa—you’ll see why people get hooked.

Once you understand their temperament, you’ll have a much easier time working with them. We always say: know your plant, grow your plant.

Getting the Soil Right Before You Plant

Start with the soil, always. These onions won’t tolerate heavy clay or lifeless dirt. You’re aiming for soil that breathes, drains well, and is rich with organic matter. A slightly acidic pH, somewhere between 6.0 and 7.0, is the sweet spot.

Now, let’s talk prep. First, test your soil. Don’t skip this—it tells you exactly what you’re working with. Then dig in compost or well-aged manure until the soil feels fluffy and full of life. You should be able to run your fingers through it without resistance.

When it’s time to sow, we go for about a half-inch deep. Seeds should sit about an inch apart, and rows spaced between 12 to 18 inches to give each plant its breathing room. That extra space helps with airflow, which keeps disease at bay and your crop happy.

Planting Seeds the Way We Do It

Starting from seed is our go-to—not just because it saves money, but because we like the control it gives us. We typically begin indoors, about 8 to 10 weeks ahead of the last frost.

Here’s our basic rhythm:

1. Fill seed trays with a light, well-draining mix.
   

2. Plant the seeds roughly 1/2 inch deep and 1 inch apart.
   

3. Keep the soil moist (not soggy) and under steady light—sunny windows work, but grow lights are better.
   

4. Once those first true leaves appear, it’s time to harden them off and transplant outdoors.
   

5. Out in the garden, we give each seedling about 4 to 6 inches of space. Trust us, they’ll use it.
   

It’s a bit of patience up front, but come harvest, it’s worth every minute.

Caring for Your Walla Walla Seedlings Without Fuss

These little guys love attention—just not too much of it. Keep the watering consistent. You want the soil damp but never soaked. As they grow, ease off on water a bit so they can bulk up underground.

We usually mulch lightly around the base of the plants. This keeps the moisture even and suppresses weeds that might try to elbow their way in. Watch out for pests, though—they tend to show up just when things are going smoothly.

The key is consistency. Small acts, repeated often, lead to robust, tasty bulbs.

A Final Word on Growing Walla Walla Onions from Seed

There’s a rhythm to growing Walla Walla onions that we’ve come to love. It’s a process that asks for attention, but never demands perfection. With the right setup, a dash of persistence, and a few trial-and-error seasons under your belt, you’ll be growing sweet, full-flavored onions like a pro.

Stick with what works: good soil, steady light, and well-timed care. You’ll taste the difference in every bite. Whether you’re dreaming of adding them to your backyard bounty or want to test your green thumb on something new, Walla Walla onions offer the perfect blend of challenge and reward.

So get out there, plant with confidence, and enjoy the satisfaction that comes from growing something truly special with your own two hands.