Onion - Allium cepa (Care, Characteristics, Flower, Images, Edible)

Onion

Also known as: Garden onion, Common onion

Onion (Allium cepa) is an onion species commonly known for its ubiquitous culinary applications. The onion is toxic to a variety of animals. Aside from its many culinary uses, the onion is often used to teach students how to use a microscope because its cells are very large and easy to visualize.

Scientific classification

Species

Onion (Allium cepa)

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Toxic to Pets

Toxicity

Perennial, Annual, Biennial

Lifespan

Herb

Plant Type

Summer

Bloom Time

Early spring, Mid spring, Summer, Early fall, Mid fall

Harvest Time

15 cm to 45 cm

Plant Height

15 cm to 30 cm

Spread

Green

Leaf Color

2.5 cm

Flower Size

Brown, Black

Fruit Color

White

Flower Color

Green, White, Brown, Cream

Stem Color

Summer dormancy, Winter dormancy

Dormancy

Deciduous

Leaf type

20 - 38 ℃

Ideal Temperature

Summer

Growth Season

Images of Onion

Distribution of Onion

Distribution Map

Onion is native to central Asia, possibly in the area that today is Turkmenistan. It is now spread quite widely across the northern hemisphere and is present in much of North America, Europe, North Africa, and Asia. It is extinct in the wild, but has been widely cultivated for 7,000 years.

Native

Cultivated

Invasive

Introduced

No species reported

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Habitat

Cultivated Beds

Hemisphere Trend Curve

Northern

Sorthern

Culture

Garden Use

Onion is an easy-care onion variety that finds a popular place in many vegetable gardens. Its pretty tall-stalked flowers also bring eye-catching color to ornamental gardens. The flowers will attract bees, and they are lovely when cut for a vase. Leave room for natural propagation, but they pair well with wild grasses.

Symbolism

Protection, Exorcism, Healing

Name Story

Garden onion: Cepa is commonly accepted in latin for "onion" and has an affinity with Ancient Greek. It is the most widely cultivated species of the genus Allium and many people treat it as a garden vegetable. Therefore, it is called the garden onion.

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Cultivars

There are several recognized cultivars of Onion, including the following common varieties :

Garden onion 'Red Baron'Garden onion 'Sturon'Garden onion 'Redspark'Garden onion 'Yellow Moon'Garden onion 'Centurion'

Toxicity

Onion is highly toxic to cats. All parts, including cooked, can cause vomiting, diarrhea, and pale gums within 6-12 hours, requiring veterinary care. Dogs also experience gastrointestinal distress from onion, especially the bulb, causing vomiting and diarrhea. All parts are toxic to both species but are rarely fatal for dogs.

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Quickly Identify Onion

Cream-colored oval bulbs, 2-3 inches (5-7.5 cm) long with red, purple, or brown skin.

Chive-like green tops with multiple offsets and deer/rabbit resistance.

Small white/pink star-shaped flowers in spheroid clusters, 0.8-3 inches (2-8 cm) wide.

Dry capsules with black, wrinkled seeds, 0.2-0.24 inches (4-6 mm) wide.

Hollow tubular stem, 0.5-1 inch (1.3-2.5 cm) wide, green to bluish-green.

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Care Guide for Onion

Every 1-2 weeks

Water

Full sun

Sunlight

20 - 38 ℃

Ideal Temperature

Garden Soil

Soil Type

Water: Onion grows best in a balanced moisture environment, needing moderate watering every 1-2 weeks. Adequate water during the growing season is essential for bulb development and overall plant health, particularly when grown outdoors.

Fertilize: Onion requires phosphorus and potassium-rich fertilizers, ideally a 10-20-10 NPK mix, applied every 4 weeks during growth in spring and summer. Use 1 cup per 20 feet, avoiding bulb contact. Water after application and wear gloves for safety.

Pruning: Onion has a bulbous form and needs minimal pruning, ideally in early spring by removing dead leaves. Prune during active growth to reduce disease risk. Avoid cutting the main stalk for proper bulb development. Regular pruning leads to healthier, more resilient plants.

Propagation: Onion is propagated via tubers in Spring. Success is shown by new green shoots. Proper planting depth and adequate moisture are essential for optimal growth.

Repotting: Repot the bulbous onion every 2-3 years, ideally post-harvest. Select a pot slightly larger than before and use well-draining soil to prevent rot. After repotting, maintain moist soil and provide ample sunlight for optimal recovery and growth.

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