Almagro Onion is a classic storage onion that matures in about 100 days, producing reliable bulbs across a wide range of climates from zones 3 to 10. This frost-hardy cultivar thrives in cool conditions and rewards patient gardeners with onions that cure beautifully for long-term storage. Direct sow in spring or start indoors for transplanting, spacing plants just 2 inches apart in rows 12 inches wide, and you'll have a steady supply of this dependable variety.
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Almagro is a true workhorse onion, the kind that stores for months without fuss and grows reliably in challenging climates where other varieties struggle. Its frost-hardy nature means you can push the growing season further in cool regions, and the 100-day maturity gives you flexibility in planting windows. The tight spacing requirement means you can grow more plants in a small footprint, making it especially valuable for gardeners working with limited beds.
Almagro onions are primarily grown as storage bulbs for kitchen use, prized for their long shelf life and reliable performance in cool climates. They work well in any dish calling for a sturdy cooking onion, from soups and stews to roasted preparations where their firm texture holds up through extended cooking.
No timeline data available yet for this variety.
Sow up to 10-12 seeds in a 4- to 6-inch pot at temperatures between 50 and 70°F. If seedling tops reach over 5 inches before transplanting, cut them back to 3 inches to encourage stronger root development. Time indoor seeding so transplants are ready to move outside at the proper season for your zone.
When seedlings are established, carefully separate them and place in a shallow trench at spacing of 2 inches apart with 12 inches between rows. Backfill the trench gently around the seedlings and water in well to establish good soil contact.
Direct sow seeds outdoors when soil is workable in spring. Thin to the strongest plant when seedlings reach 4 to 5 inches tall, leaving 2 inches between plants.
Almagro onions are ready to harvest around 100 days after planting. As bulbs mature, watch for about half the tops to naturally fall over, then push over any remaining tops that haven't fallen. Wait approximately one week after this, then harvest in dry weather. Loosen the soil around bulbs gently before pulling to reduce damage. Avoid harvesting onions in wet conditions, as they will not cure properly and may rot during storage.
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