- Variety Info
- Sowing Info
- Growing Info
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Variety Info
Days to Maturity: 100–125 days
Family: Alliaceae
Type: Long-day sweet onion. (Learn more)
Native: Exists only in cultivation
Hardiness: Biennial grown as an annual
Exposure: Full sun
Plant Dimensions: 4" to 6" slightly-flattened bulbs with 6" to 10" tops
Variety Info: Yellow, slightly flattened, globe onion, 4"–6" in diameter and weighing around 2 lbs. with dry, papery skin and 6"–10" tops. 'Walla Walla' is a bulbing, yellow, long-day, sweet onion with a short storage period.
Attributes: Frost Tolerant
Sowing Info
When to Sow Outside: 4 to 6 weeks before your average last frost date, or as soon as soil can be worked; when soil temperature is at least 45°F.
When to Start Inside: RECOMMENDED. 10 to 12 weeks before your average last frost date. Transplant outdoors 4 to 6 weeks before your average last frost date. The earlier the start, the bigger the bulb. Ideal soil temperature is 60°–85°F.
Days to Emerge: 7–15 days
Seed Depth: ¼"
Seed Spacing: A group of 2 seeds every 6"–8"
Row Spacing: 12"–16"
Thinning: When 2" tall, thin to 1 every 6"–8"
Your hardiness zone is
Growing Info
Harvesting: When onion tops have fallen over and turned yellow or brown, they are ready for harvest. Harvest in the morning, lifting onions with a garden fork. Dry them in the garden in the sun for 2 to 3 days, lightly covering the bulbs with straw, or the tops of other onions to prevent sunscald. Cure onions for 3 to 7 days in a dry area with good air circulation. Once dry, cut the roots to 1/4", and the greens to 1" to create a seal, preventing decay.
- Debra L.Verified BuyerRated 5 out of 5 stars3/5/26Growing well
So far seedlings are doing well. Won't really know until I see a harvest.
Which best describes you as a gardener? IntermediateBIBotanical Interests3/6/26Hey Debra,
We're so happy to hear your Walla Walla Bulb Onion seedlings are doing well! You're absolutely right that the real test comes at harvest time, but healthy seedlings are a fantastic start. Thank you for choosing us and for sharing this encouraging update with us. Keep on growing 🌻️
- Lorey B.Verified BuyerRated 5 out of 5 stars11/4/25Onion seeds
Growing quite well.
Which best describes you as a gardener? Intermediate - Lex ..Verified BuyerRated 5 out of 5 stars3/23/255 Stars
Great germination rate, almost 100%! The onion seedlings look very healthy. I used Fort Vee seedling mix, and am trimming the seedlings for better growth. I’m happy with these!
- Clay C.Verified BuyerRated 1 out of 5 stars6/12/241 Star
Onions did not propagate well at all. I didn’t have any to plant
Which best describes you as a gardener? IntermediateBIBotanical Interests6/13/24Hey Clay,
I sincerely appreciate you taking the time to share your thoughts in a review. I've reached out to you via email to offer assistance and address any concerns you may have. Your feedback is invaluable to us, and we are committed to ensuring your experience is positive. Thank you once again for your input. Keep on growing 🌻️
- Norman D.Verified BuyerRated 5 out of 5 stars5/1/245 Stars
So what does matter to a home gardener when choosing a catalogue from which to order seeds? For me it is knowing that my order will be processed and shipped el pronto quicko. It is knowing that the germination rate of the seed I have ordered approaches 80% or higher. It is knowing that they are not about selling odd ball novelty varieties but about providing rock solid varieties with proven performance. They almost always have whatever I am looking for. Botanical Interests has been my go to resource for seeds for 3 years and they have never disappointed.
Which best describes you as a gardener? Expert