ONION-WHITE SWEET SPANISH

How to grow White Sweet Spanish Onions

1. Select a sunny spot that receives at least 6-8 hours of direct sunlight daily.
2. Use fertile, well-drained loamy or sandy soil.
3. Adjust pH to 6.0-7.0 for optimal growth.
4. Work compost or well-rotted manure into the top 15-20 cm (6-8 inches) of soil.
5. Plant Seeds directly or start indoors 6-8 weeks before the last frost. 
6. Raise seedlings at a soil temperature of 13-24°C (55-75°F).
7. Planting Depth 1-1.5 cm (0.4-0.6 inches) deep
8. Space plants 10-15 cm (4-6 inches) apart and rows 30-45 cm (12-18 inches) apart.
9. Optimal growing temperature is 13-25°C (55-77°F).
10. Seedlings tolerate light frost but protect plants from prolonged freezing.
11. Water consistently to keep the soil moist but not waterlogged. 
12. Reduce watering as the bulbs mature to prevent rot.
13. Apply a nitrogen-rich fertilizer every 3-4 weeks during early growth.
14. Reduce nitrogen in later stages to promote bulb development.
15. Cover with 2-3 cm (1 inch) layer of organic mulch to retain soil moisture and suppress weeds.
16. Weed regularly to minimize competition for nutrients and sunlight. 
17. Inspect plants for pests like onion maggots or thrips and use organic sprays or companion planting for protection. 
18. Practice crop rotation to prevent fungal diseases like downy mildew. 
19. Bulbs are ready to harvest 100-120 days after planting . 
20. When the tops yellow and fall over, gently pull bulbs from the soil.   
21. Cure bulbs in a warm, dry, and ventilated area (21-27°C or 70-80°F) for 10-14 days.  
22. Store cured onions in a cool, dry place (2-4°C or 35-40°F) for long-term use.

Additional growing tips for White Sweet Spanish Onions

• Push the Soil Back from the Bulbs as the bulbs start to form to allow more exposure to air and prevent rot. This practice, called “bulb popping,” can lead to larger, healthier onions.
• Don’t Bend the Tops Too Soon  or you can stunt bulb growth. Let the tops naturally yellow and fall over on their own for best results.
• Trim Seedlings for Stronger Growth if you are starting seeds indoors.  Trimming to 7-8 cm (3 inches) tall encourages thicker, sturdier stems and prevents them from becoming leggy.
• Onions Love Epsom Salt (magnesium sulfate) sprinkled around the plants to promote strong roots and improve bulb development. Use sparingly—about 1 tablespoon per square meter (10 square feet).
• Sprinkle  Ash for Pest Control around the base of onion plants to deter pests like onion maggots and slugs while also adding potassium to the soil.
• Rotate Crops Religiously as onions are heavy feeders and prone to soil-borne diseases.  Never plant them in the same spot two years in a row; rotate with legumes or leafy greens for healthier crops.
• Avoid Over-Fertilizing with Nitrogen which encourages lush green tops but results in small bulbs.  Switch to a low-nitrogen fertilizer or stop fertilizing altogether once the bulbs start to swell.
• Use Coffee Grounds mixed into the soil to provide slow release of nitrogen and improve soil texture. This practice has been reported to encourage steady onion growth.
• Companion Plant with Marigolds as a natural deterrent to thrips and aphids, making them a great addition to your onion patch.
• Harvest according to Moon Phases during the waning moon phase, which is said to helps with better curing and storage longevity.
• Singling Out Crowded Plants gives more room for bulbs to grow but also provides young green onions for fresh use. These “thinnings” are sweet and tender!
• Spraying with Compost Tea  as a foliar spray (made from steeped compost) can give onions a mid-season nutrient boost, improving both growth and resistance to disease.
• Don’t Water Right Before Harvest to allow the onions to “cure” slightly in the soil. This prevents bulbs from becoming too moist, which can lead to rot during storage.
• Be Patient for Bigger Bulbs  which  grow significantly in the final 2-3 weeks before harvest. Resist the urge to harvest too soon.

Heritage of White Sweet Spanish Onions

White Sweet Spanish onions are a classic variety with a heritage rooted in traditional farming practices. They originated in Spain, renowned for cultivating large, mild, and sweet onions. Spanish onions gained popularity for their versatile culinary uses, from fresh salads to caramelized dishes. Their large white bulbs and sweet flavor profile make them a preferred choice for onion enthusiasts worldwide. Over generations, this heirloom onion variety has been valued for its excellent storage capacity and adaptability to diverse climates, continuing to be a staple in home gardens and commercial agriculture alike.

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