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Yellow Sweet Spanish Onion Seeds – Heirloom Long-Day Variety for Large, Sweet, Mild Bulbs

Heirloom - Non-GMO - Reliable Germination

$3.49 USD
Shipping calculated at checkout.
Size: 1 Packet

What Makes Survival Garden Seeds Different - non-GMO heirloom seeds

Grow classic, sweet onions with Yellow Sweet Spanish Onion Seeds from Survival Garden Seeds. This heirloom long-day variety produces large, golden bulbs with a mild, pleasant flavor that works beautifully in both fresh and cooked dishes. Easy to grow and highly productive, Yellow Sweet Spanish is a long-time favorite among home gardeners for its reliable yields and adaptable nature.

Vigorous and Adaptable:
Yellow Sweet Spanish onions mature into sturdy, resilient plants known for their consistent performance in a wide range of garden settings. Whether grown in containers, raised beds, or traditional garden rows, this variety reliably produces abundant harvests. Its adaptability and strong growth habit make it a top choice for gardeners seeking dependable results.

Sweet, Mild Flavor for Everyday Cooking:
These onions are prized for their balanced sweetness and versatility. Their large bulbs and mild flavor make them ideal for salads, sautés, soups, roasts, grilling, and countless home-cooked meals. Yellow Sweet Spanish brings a familiar, classic onion character that complements nearly any recipe.

Why Customers Love Yellow Sweet Spanish Onion:

  • Produces large, sweet, mild onions
  • Heirloom long-day variety with strong yields
  • Adaptable to containers and in-ground gardens
  • Reliable and vigorous growth habit
  • Versatile flavor for fresh and cooked dishes

How to Grow:
Start seeds indoors 8–10 weeks before your last frost date, keeping seedlings evenly moist and well lit. Transplant outdoors once the soil can be worked and temperatures begin to warm. As a long-day variety, Yellow Sweet Spanish forms full bulbs in northern regions where summer daylight lasts 14–16 hours. Plant in full sun with loose, well-drained soil, water consistently, and maintain weed-free beds to support steady growth. Harvest when bulbs reach full size and tops naturally fall.

Net Wt. 500MG

Heirloom Vegetable Seeds

All of our seeds are open-pollinated, non-GMO, heirloom varieties with tested germination rates

Specifications

  • Botanical Name
    Allium cepa
  • Planting Zones
    3-6
  • Light
    Full Sun
  • Soil Temp for Germination
    75 Degrees F
  • Germination Time
    8-14 Days
  • Planting Depth
    1/2 Inch
  • Plant Size
    12-18 Inches Tall, 6-8 Inch Spread
  • Days to Harvest
    115-130 Days
  • Growing Instructions
    Start indoors 8-10 weeks before transplanting outside, or sow directly outside once the ground can be worked. Keep evenly moist until well established. Trim leaves to 3" when transplanting to focus growth in roots. Plant seedlings 2" deep and space 4-6" apart.
  • Seed Saving Instructions
    Onions are biennial, flowering in the second year. In autumn, mulch heavily or replant chosen bulbs in spring. Once flowering heads turn brown, clip and place in a paper bag and dry for several weeks. Separate and store in a cool, dry place.
  • Seed Count (approximate)
    112 to 130

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Why Choose Survival Garden Seeds

At Survival Garden Seeds, we believe in preparing today for tomorrow’s peace of mind. That’s why we offer only heirloom, non-GMO, and untreated seeds you can trust to nourish your family and support a sustainable lifestyle. As a family-owned American company, we’re committed to providing seeds that grow strong and true—helping you cultivate health, resilience, and beauty in your garden.

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Frequently Asked Questions

Are your seeds heirloom and open-pollinated?

Yes. All of our seeds are heirloom, open-pollinated varieties, which means they can produce seeds that grow true to type and are suitable for seed saving.

You can learn more about open-pollinated, heirloom, and non-GMO seeds in our Survival Garden Training blog.

Are your seeds non-GMO?

Yes. All Survival Garden Seeds are 100% non-GMO. Our seeds are open-pollinated heirloom varieties and are never genetically modified.

Are your seeds treated with chemicals?

No. Our seeds are completely untreated and free from chemical coatings, fungicides, or synthetic treatments.

How do I know my seeds are fresh?

Every seed packet includes a packed-for date, and we germination-test each seed lot before packaging to ensure high viability.

What is the shelf life of your seeds?

Most seeds remain viable for 3 to 5 years or longer when stored properly in a cool, dry place away from light and moisture.

In what USDA hardiness zones can I grow your seeds?

Our varieties are selected to grow successfully across USDA Hardiness Zones 3 through 10. Each packet includes variety-specific planting guidance and germination tips.