Early White Grano PRR is a sweet white onion developed by Texas A&M Agricultural Experimental Station, bred specifically for resistance to Pink Root Rot. This large Vidalia-style bulb matures in 100 to 109 days and grows 14 to 24 inches tall, thriving across hardiness zones 2 through 9 in full sun. An open-pollinated heirloom variety, it descends from the famous Texas Early Grano 502 and brings both heritage reliability and modern disease resistance to the home garden.

Photo © True Leaf Market
3
Full Sun
Moderate
2-9
24in H x ?in W
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Moderate
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This onion carries the sweetness and mild flavor of Vidalia-type onions while adding what Texas A&M breeders worked to achieve: genuine resistance to Pink Root Rot, a disease that can devastate onion crops. Unlike the original Early Grano 502, the PRR designation means gardeners in disease-prone regions can grow this variety with confidence. The large white bulbs store well and perform across a remarkably wide range of climates, from zone 2 cold to zone 9 heat.
As a fresh eating onion, Early White Grano PRR shines sliced raw into salads and sandwiches, where its sweetness and mild flavor do not overpower delicate greens or vegetables. Its large size and low pungency make it well suited to grilling or roasting whole, where the natural sugars caramelize into deep, rich flavor. The bulbs store reliably for months under cool, dry conditions, so fresh onions remain available long after harvest.
No timeline data available yet for this variety.
Start seeds indoors 10 to 12 weeks before your last spring frost, planting them at a depth of approximately 1/4 inch in seed-starting mix kept consistently moist. Provide bright light and temperatures around 70°F (21°C) to encourage germination and vigorous seedling growth.
Harden off seedlings over 7 to 10 days by gradually exposing them to outdoor conditions. Transplant to the garden after the last frost danger has passed and soil is workable. Set transplants 3 inches apart in rows 15 inches wide, burying them deeply enough that the base sits firmly in soil but the green shoots remain above ground.
In mild climates, direct sow seeds outdoors in early spring as soon as soil can be worked, planting at 1/4 inch depth. Direct-sown onions typically develop smaller bulbs than transplants, so transplanting is generally preferred for maximum size.
Harvest Early White Grano PRR onions after 100 to 109 days when the tops begin to yellow and fall over naturally, typically in late summer. You can gently bend the tops over to speed the ripening process once the plants begin to senesce. Pull the bulbs from the soil on a dry day and cure them in a warm, well-ventilated location for 2 to 3 weeks until the outer skins papery completely and the neck dries fully. Store the cured bulbs in a cool, dry place for extended use.
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“Early White Grano PRR emerged from deliberate breeding work at the Texas A&M Agricultural Experimental Station, where researchers crossed the beloved Texas Early Grano 502 with germplasm selected for Pink Root Rot resistance. The goal was straightforward but important: preserve the sweet, mild character that made Early Grano famous while eliminating the vulnerability that plagued growers. The result is a variety that honors its Texas heritage while solving a real problem gardeners face in the field.”