What are the sun requirements for Allium cepa 'Granex'?

Allium cepa 'Granex' is Granex onion (Vidalia-type onion), a biennial grown as an annual for bulb production, 18-24 inches (45-60 cm) tall and 4-6 inches (10-15 cm) wide. Flattened globe-shaped bulbs 3-4 inches (7-10 cm) diameter with golden-yellow papery skins and white to pale yellow flesh. A sweet onion: reduced sulfur compounds — mild enough to eat raw. Blue-green hollow tubular foliage. In the amaryllis family (Amaryllidaceae). A short-day onion: bulbs at 10-12 hours of daylight (latitudes below 35°N) — the standard type for the deep South, Gulf Coast, and southern California. The Granex type is the parent cultivar behind the Vidalia onion — true Vidalia onions are Granex-type cultivars grown in a 20-county region of southeastern Georgia where low-sulfur soil produces the mild flavor. F1 hybrid — seed does not produce true to type. Stores only 1-2 months — the shortest storage of any onion type due to high water content and thin skins. Use fresh. Start seed indoors 10-12 weeks before last frost, or fall-plant in zones 7-10. Harvest when 50-75% of tops have fallen (90-120 days from transplant). All Allium contain thiosulfates: toxic to dogs, cats, and horses. Thrips and onion maggot (Delia antiqua) are primary pests. Deer-resistant. Full sun. Annual. Growth rate is moderate.

Native Range

F1 hybrid cultivar developed by Asgrow Seed Company. The species A. cepa is native to Central Asia.

Suggested Uses

Grown in vegetable gardens and containers of at least 3 gallons (11 L). Short-day sweet onion (latitudes below 35 degrees N). The Vidalia parent type. Stores only 1-2 months — use fresh. F1 hybrid. Toxic to pets. Deer-resistant. Annual.

How to Identify

Identified by flattened globe-shaped bulbs with golden-yellow papery skins and mild sweet white flesh on a plant with blue-green hollow tubular foliage. The flattened shape and the short-day requirement (10-12 hours) distinguish Granex from long-day types. The Vidalia onion parent type. In Amaryllidaceae.

Appearance

Size & Dimensions

Height1'6" - 2'

Width/Spread4" - 6"

Reaches mature size in approximately 1 years

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Biennial: flowers in the second year if overwintered — white spherical umbels. Grown as an annual for bulb production. Cut flower scapes at the base if they appear.

Detailed Descriptions

Flower Description

White spherical umbels on a hollow scape — only if allowed to bolt; undesirable in bulb production

Foliage Description

Blue-green, hollow tubular, 0.5-0.75 inch (12-18 mm) diameter; yellows at maturity

Growing Conditions

Sun Requirements

Full Sun

Requires 6-12 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.0 - 7.0(Neutral)

357912

Soil Types

loam

Drainagewell drained

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Time to Maturity

90-120 days from transplant

Care & Maintenance

Care Guide

Full sun (6+ hours). Well-drained soil pH 6.0-7.0. Short-day onion — 10-12 hours daylight (latitudes below 35 degrees N). Fall-plant in zones 7-10, or spring-plant in mild climates. Consistent moisture during bulb swelling. Stores only 1-2 months — use fresh. F1 hybrid. All Allium toxic to pets. Deer-resistant. Annual.

Pruning

Cut flower scapes at the base if they appear. Do not cut green foliage during growth. Harvest when 50-75% of tops have fallen. Trim tops to 1 inch (2.5 cm). Cure 1-2 weeks only (thin skins).