Onion Seeds - Long - Utah Yellow Sweet Spanish


110-115 Days to maturity. Allium cepa. Variety name Onion Seeds. Non-GMO, annual, open-pollinated, heirloom, cold tolerant, bulbing, long-day onion. Suitable for growing in greenhouses, garden plots, raised beds, and containers. This yellow onion is considered a long-day type and may be grown in intermediate-day regions as well. Recommended by Utah State University and is the state vegetable of Utah. Large bulbs weighing over a pound have great storage capabilities. This Spanish Onion is relatively easy to grow with moderate pink root tolerance. ~7,000 seeds per ounce.

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How to Grow Utah Yellow Sweet Spanish Onion from Seed

Onion is a cool hardy vegetable that can be sown directly 6-8 weeks prior to final spring frost or about 4-6 weeks before the first autumn frost. Seeds may also be begun indoors for early starts. Soil should be well-tilled, nitrogen-rich, with a pH of 6.0-7.0. For outdoor sowing, create a shallow 1" deep trench for a minimum of 12".

Onion seed is very small, so sprinkle generously into the trench and lightly cover with about 1/4" of soil. As seedlings begin to sprout from the row, trim back to favor the strongest starts every 4-6" apart. "“Long-day" onions grow best in the northern half of the country while "“short-day" thrives in the southern half.

Utah Spanish Onions take about 115 days to mature after planting seeds in the ground. Wait until the ground is not frozen, and is between 60-85°. Onions thrive in soil that drains well but still needs to be dense in nutrients. As the onion grows, you will see green sprouts appear. Allow the tops of onions to fall and die before harvesting your crop. If any bulbs are too small to be consumed they can be saved and planted next year. A mature Utah Yellow Spanish Onion will have light brown skin and white flesh.

Utah Yellow Sweet Spanish Onion in the Vegetable Garden

Onion is a cold hardy favorite able to be sown in either spring or fall for an effortless biannual harvest. Onions are often started in the garden from store-bought bulbs, but growing from seed allows for a greater variety of selection among the red, yellow, white, and sweet cultivars.

When planting, look to see if a "“long-day" or a "“short-day" onion variety is best suited for the summers in your region. Try an onion crop in the garden bed alongside similar garlic, shallots, or leeks.

Harvesting Utah Yellow Sweet Spanish Onion

Most onions sown in the spring are ready for harvest about 90 days from sowing and seeds planted in the fall can mature as early as May or June the following year. Onions are ready to harvest once the plants" greens have dried out, yellowed, and begun to bow over. Loosen the soil from the bulb to check for consistent coloring while allowing the bulb to further dry. Sweet onions do not store as well as more pungent yellow and brown varieties.

About Utah Yellow Sweet Spanish Onion Seeds

Long Day Variety. Large yellow bulbing onion that has a mild sweet flavor. Can get up to 6" across and weight over a pound or more.

It is a good keeper as well for those country cooks!

It is important to dry your onions in the garden first for proper storage. Pull them up on a sunny day and let them dry in the sun for two days to cure. Then store them.

Onion seed has a short shelf life so keep it cool and dry.

The Utah Yellow Spanish Onion is a great slicing onion. It goes perfect on Patty Melt and is great as a grilled onion. Spanish Onions are known for being large and these onions make great onions for sandwiches as well. Delicious in marinara, chili, or stew.

Utah Yellow Sweet Spanish Onion Seeds Per Package:

  • 2 g - Packet - Approx 500 Seeds
  • 1 oz- Wholesale - Approx 7,000 Seeds
  • 4 oz - Wholesale - Approx 28,000 Seeds
  • 1 lb - Wholesale - Approx 112,000 Seeds
  • 5 lb - Bulk - Approx 560,000 Seeds
  • 25 lb - Bulk - Approx 2,800,000 Seeds

Non-GMO Utah Yellow Sweet Spanish onion seeds are available for Fast Free Shipping on orders over $75.

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