Customer Service Hours
Mon-Fri 8-4 MST
Features
Family
Alliaceae
Native
Exists only in cultivation
Life Cycle
Annual
Plant Height
3 1/2" to 6" globe-shaped bulbs with 12" to 16" tops
Further Information
Growing Conditions
Frost Tolerant
About Onion
Allium cepa
Large, 3 ½"–6", up to 2 lbs., pale yellow, globe-shaped bulbs with coppery wrapper; 12"–18" tops. 'Yellow Sweet Spanish Utah' is a bulbing, yellow, long-day onion with a moderate storage period.
Planting Onion
Plant Spacing
A group of 2 seeds every 6"–8"
Light Required
Full sun
Plant Height
3 1/2" to 6" globe-shaped bulbs with 12" to 16" tops
Planting Depth
¼"
Coverage & Planting Details
| Coverage | This packet sows up to 30 feet. |
|---|---|
| Row Spacing | 12"–16" |
| Seed Depth | ¼" |
| Seed Spacing | A group of 2 seeds every 6"–8" |
| Thinning | When 2" tall, thin to 1 every 6"–8" |
| Germination | 7–15 days |
| Start Indoors | 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. |
| Direct Sow | 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. |
| Growing & 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. |
Find Your Frost Date & Grow Zone
Average First Frost Date
October 19
Average Last Frost Date
May 19
Your Hardiness Zone is
5b
Send Your Recommendation
Total 5 star reviews: 9 Total 4 star reviews: 4 Total 3 star reviews: 1 Total 2 star reviews: 0 Total 1 star reviews: 2
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Rating
Which best describes you as a gardener?
16 reviews
- Debi U.Verified BuyerRated 4 out of 5 stars4/15/26Seeds are growing.
The seeds were slow to germinate but doing well. I started them inside and will plant soon. I’m in zone 4b so still not ready to plant out.
Which best describes you as a gardener? IntermediateBIBotanical Interests4/15/26Hey Debi,
We're so glad to hear your Yellow Sweet Spanish Utah Bulb Onion Seeds are doing well after their slow start! Sometimes onion seeds just need a little extra time to get going, but once they do, they're such rewarding growers. Your seedlings look great! Starting them inside is such a smart move for zone 4b - you'll have strong transplants ready to go when your weather warms up! These sweet Spanish beauties are going to produce some amazing onions for your kitchen. Keep on growing 🌻️
- MatthewRated 5 out of 5 stars4/2/265 Stars
Everything came here great!
- DVerified BuyerRated 3 out of 5 stars9/18/2561% germination rate
Planted 23 seeds on 8/29, 14 germinated very quickly. The others never germinated. Planted the 14 onions outside 9/18.
Which best describes you as a gardener? IntermediateBIBotanical Interests9/19/25Hey D,
Thank you so much for taking the time to share your thoughts in a review. I've reached out to you via email to offer assistance. 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 🌻️
- DVerified BuyerRated 5 out of 5 stars9/2/25Very Fast Germination
Planted 8/29, sprouted 9/2
Which best describes you as a gardener? IntermediateBIBotanical Interests9/2/25Hey D,
Thank you so much for sharing your amazing germination results with our Yellow Sweet Spanish Utah Bulb Onion Seeds! We absolutely love hearing that you got such incredibly fast sprouting - just 4 days from planting to emergence is fantastic! That's exactly the kind of vigorous performance these quality onion seeds are known for. There's nothing quite like seeing those first little green shoots pop up so quickly - it really gets the growing season off to an exciting start! With germination like that, you're definitely on track for some beautiful, large sweet onions. Keep on growing 🌻️
- Jayne S.Verified BuyerRated 5 out of 5 stars2/8/255 Stars
This company does it all for me. Great seeds that always meets my expectations. Beautifully artistic seed packets for that inspiration motivation. (I even made a framed collage of some of the seed packets for my wall. I got many compliments on it too!). Great customer service. Onions are extremely easy to grow. These have great flavor.