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ALLIUM cepa 'Granex'

Image of Allium cepa 'Granex'

Family

Liliaceae

Botanical Name

ALLIUM cepa 'Granex'

Plant Common Name

Garden Onion, Yellow Onion

General Description

The classic Spanish sweet onion, 'Granex', is yellow-fleshed, has a sweet flavor and crisp texture. In fact, it is among several favored cultivars of sweet onions grown in the Vidalia, Georgia region each year and dubbed "Vidalia onions."

The garden onion is a biennial or perennial widely grown as an annual vegetable. This variety produces a dense upright cluster of hollow pale green leaves that rise from a yellow, papery bulb that grows larger and more bulbous as the season progresses. Round clusters if white, star-like flowers emerge from plants in the spring of the second year, though these are rarely seen because plants are harvested after the first year.

Onions are categorized according to the day length needed for bulb formation. Granex onions require short days (10 to 12 hours) to form large onions. They are thus usually planted in fall or early winter, for harvest in spring and early summer, which is why they are typically grown in the south. They are usually sweet, but do not store or keep well and should be eaten soon after harvest.

Full sun and regular water are needed for good growth and production and loose, rich, well-drained soil with a neutral pH is preferred. There are a number of pests and diseases that can be problematic including downy mildew, smut and onion maggots. If you are planting onions from sets, or small bulbs, plant the bulbs just below the surface, with the neck showing. When most of the leaves begin to turn yellow, dig the bulbs and dry them in a shady well-ventilated place for several days before storing.

Characteristics

  • Sunset Zone

    A1, A2, A3, H1, H2, 1a, 1b, 2a, 2b, 3a, 3b, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24

  • Plant Type

    Vegetable

  • Sun Exposure

    Full Sun, Partial Sun

  • Height

    2'-3' / 0.6m - 0.9m

  • Width

    4"-12" / 10.2cm - 30.5cm

  • Bloom Time

    Late Spring, Early Summer

  • Native To

    World/Pandemic, North America, Europe, Russia/Siberia, Northern Africa, Asia, India

Growing Conditions

  • Soil pH

    Neutral

  • Soil Drainage

    Well Drained

  • Soil type

    Loam, Sand

  • Growth Rate

    Fast

  • Water Requirements

    Average Water

  • Habit

    Upright/Erect

Ornamental Features

  • Flower Interest

    Showy

  • Flower Color

    White, Yellow Green

  • Foliage Color (Spring)

    Green, Gray Green

  • Foliage Color (Summer)

    Green, Gray Green

  • Foliage Color (Fall)

    Green, Gray Green, Yellow Green

  • Foliage Color (Winter)

    Light Green

  • Fragrant Flowers

    Yes

  • Fragrant Fruit

    No

  • Fragrant Foliage

    Yes

  • Bark or Stem Fragrant

    Yes

  • Flower Petal Number

    Single

  • Repeat Bloomer

    No

  • Showy Fruit

    No

  • Edible Fruit

    No

  • Showy Foliage

    No

  • Foliage Texture

    Medium

  • Foliage Sheen

    Matte

  • Evergreen

    No

  • Showy Bark

    No

Special Characteristics

  • Usage

    Edible, Herb / Vegetable

  • Sharp or Has Thorns

    No

  • Invasive

    No

  • Self-Sowing

    No