Planting Walla Walla Onions: Things You Need to Know

Learn fun facts about the Walla Walla onion, and find out how to grow this sweet, juicy onion out in your garden and in containers indoors.

Sean Stratton | Updated April 23, 2023
a bunch of onions

Walla Walla onions are tasty and filled with calcium, potassium, vitamin C, fiber, and other micronutrients.

You can quickly grow them with little effort and enjoy fresh onions for your salad directly from your garden.

How to Grow Walla Walla Onions

I recommend growing walla walla onions from sets. Onion sets are just young plants. They come naked-rooted (without a pot). You need to plant them quickly and water them after buying them.

1. Prepare the Soil

Choose a spot in your garden that gets full sun. Use compost to ensure proper nutrition for your plants. Losen the soil by breaking up any clumps.

2. Plant the Starts

Plant the walla walla onions in holes 1.5 inches in depth, set one inch apart from each other. Ensure the root junction is covered with one inch of soil. After planting, place soil in the base of the plants. The tip of the onion sets should be visible.

3. Water them weekly

After planting the starts, they’ll regrow in two to three weeks. You need to water them at least once weekly.

Growing Walla Walla Onions in Containers

1. Prepare the Jar

Take a container that is about 12 inches deep. Wash with water and soap. Next, rinse it with bleach and water. After air drying, mix compost and potting soil equally. Fill the container with the mixture.

2. Plant the Sets

Dig a small hole and gently push a bulb set inside it. If planting multiple sets in a large container, maintain three to four inches of distance between every bulb set.

After planting, gently cover the sets with the soil, only the tips should remain visible. Finally, move the container to a place where your onions will get at least 6 hours of direct sunlight.

3. Watering and Fertilizing

Water your plants twice weekly until you notice the leaves turn yellow. Use water-soluble fertilizer for your onions.

You can also feed them fish emulsion monthly.

4. Additional Care

Keep an eye on your plants so that spiders, slugs, or other garden pesticides don’t harm them. You can use slug bait or use copper wire around the container. For better growth, you can thin the onions five to six inches apart.

What is a Walla Walla Onion?

Walla Walla onions are sweet, yes, you heard that right! They are sweet and mild-flavored, so you can grab one, bite right into it just like an apple!

They can look globular or squat-shaped, but sometimes you may find some different shapes as well. And in size, they grow about medium to large. The juicy and sweet part of the onion is covered with flaky, paper-like skin.

The outer color of the onions ranges from light brown to yellow. Inside the outer layers, you will find the white-colored, juicy flesh, just perfect to turn into sweet onion rings!

Walla Walla onions are not so strong in flavor, rather they are mild. When you cook them, you will get a nice warm and sweet flavor, thanks to the water and high sugar content of the onions.

Walla Walla onions are not originally from the U.S., rather they are from Spain. The name ‘Walla Walla’ comes from the Walla Walla city in Washington State. In the early days of 1900, these onions were planted there for the first time. That is how Walla Walla onions got their name.

Another amazing fact about Walla Walla onions is that this crop is federally protected and they can only be grown in North Eastern Oregon or the amazing Walla Walla Valley where the onions begin their journey in the U.S. So, if you want to taste the original Walla Walla onions, you need to visit these places.

However, they can be easily grown in your backyard. You don’t need to wait for too long to put them in your salad as well. Usually, you can harvest them roughly after 125 days or a little more after planting.

Final Thoughts

Walla Walla onions are sweet which makes them different from other varieties. And the name is a fun thing to pronounce!

In this article, we talked about planting Walla Walla onions using different techniques. So, what are you waiting for? Plant Walla Walla onions this season and expect basketful sweet onions in the next harvesting season.

Written by Sean Stratton

Sean Stratton

Hi, I'm Sean, the senior editor here at Fertilizer Pick. I grew up on a farm in North Carolina and have grown fruits, vegetables, and trees since childhood. While I no longer live on a farm today, I still enjoy spending time on my garden and sharing my knowledge with friends and fellow garden enthusiasts.