Overview
Allium cepa L. var. viviparum M.C. Metz, commonly referred to as "Egyptian onion," is a subspecies of the common onion. It is known for its unique ability to produce bulbils, small onion-like growths that develop at the top of the stem in place of flowers.
Origin
The Egyptian onion is believed to have originated in the Middle East and North Africa, where it has been cultivated for thousands of years. The first recorded use of the plant dates back to ancient Egypt, where it was used for food and medicinal purposes.
Common Names
The Egyptian onion is known by a variety of names, including tree onion, walking onion, top onion, and tree garlic. These names reflect the plant's unique growth habit, in which the stem produces bulbils that eventually fall to the ground and grow into new plants.
Uses
The Egyptian onion is primarily used for culinary purposes, much like its common onion counterpart. The bulbs and bulbils can be eaten raw or cooked, and are often used in soups, stews, and other dishes. In addition to its food uses, the plant has also been used for medicinal purposes, particularly in traditional African medicine where it is believed to have antimicrobial properties.
Appearance
The Egyptian onion has a similar appearance to other onion plants, with long, thin leaves and a bulbous base. Unlike other onion varieties, the stem of the Egyptian onion is elongated and produces bulbils at the top instead of flowers. The bulbils grow on small stalks and eventually fall to the ground, where they can take root and grow into new plants. The plant itself can reach heights up to three feet tall.
Growth Conditions for Allium cepa L. var. viviparum M.C. Metz
Allium cepa L. var. viviparum M.C. Metz is a plant variety that belongs to the Allium cepa species, commonly known as the shallot. This plant variety is unique in that it produces aerial bulbs on top of the leaves instead of underground bulbs. The following are the typical growth conditions for Allium cepa L. var. viviparum M.C. Metz:
Light
Allium cepa L. var. viviparum M.C. Metz prefers full sun to partial shade. It needs at least six hours of direct sunlight per day to grow and produce a good harvest. Without enough light, the leaves may become yellow, and the plant may not produce aerial bulbs on top of the leaves.
Temperature
Allium cepa L. var. viviparum M.C. Metz grows best in cool to mild temperatures. The optimal temperature range for this plant variety is between 60 to 75 degrees Fahrenheit. Temperature above 80 degrees Fahrenheit or below 50 degrees Fahrenheit can affect the plant's growth and may cause premature flowering or bolting.
Soil Requirements
Allium cepa L. var. viviparum M.C. Metz prefers well-draining and nutrient-rich soil. The soil pH should be between 6.0 and 7.0. The ideal soil type for this plant is loamy soil, which has a good balance of sand, silt, and clay. The soil must be kept consistently moist, but not waterlogged. Overwatering may lead to rotting of the bulbs and lower yields.
To improve soil quality, you can add organic matter such as compost, manure, or leaf litter to the soil. A soil test kit can also be used to determine the soil pH and nutrient levels to ensure that the soil requirements are met.
Cultivation Methods for Allium cepa L. var. viviparum M.C. Metz
Allium cepa L. var. viviparum M.C. Metz is commonly grown in colder regions of the world, particularly in the Northern Hemisphere. Typically, it is cultivated in soil that is free of weeds, rocks, and other debris, and the area should be well-drained and receive an ample amount of sunlight.
You can grow Allium cepa L. var. viviparum M.C. Metz from seeds or by using bulbs. If growing from seeds, plant them in the spring and harvest in the fall. If you use bulbs, plant them in late summer or early fall and harvest in the following spring or summer.
Watering Needs for Allium cepa L. var. viviparum M.C. Metz
Allium cepa L. var. viviparum M.C. Metz requires moderate watering, especially during the growing season. The soil should be kept moist, but not too wet. Take care not to overwater the plant, as too much water can lead to rot and other diseases.
You can water Allium cepa L. var. viviparum M.C. Metz using a watering can or a garden hose. It is best to water the plant directly at the base, ensuring that the water is well-distributed and reaches the roots.
Fertilization of Allium cepa L. var. viviparum M.C. Metz
Allium cepa L. var. viviparum M.C. Metz requires fertilizer to grow well and produce a good yield. You can use an all-purpose fertilizer, applying it according to the manufacturer's instructions.
It is best to fertilize the plant after it has started to grow, and then once more during the growing season. Be sure to water the plant well after applying fertilizer, as this ensures that the nutrients are well-distributed throughout the soil.
Pruning for Allium cepa L. var. viviparum M.C. Metz
Pruning is typically not necessary for Allium cepa L. var. viviparum M.C. Metz. However, you may remove any yellowing or wilted leaves to improve the plant's appearance and encourage healthy growth.
If the plant is flowering and you do not want it to go to seed, you can remove the flower stalks as soon as they appear. This will redirect the plant's energy towards growing the bulbs, rather than producing seeds.
Propagation of Allium cepa L. var. viviparum M.C. Metz
Allium cepa L. var. viviparum M.C. Metz can be propagated by two different methods:
Vegetative Propagation
This method involves the use of bulbs from the parent plant. The bulbs are carefully selected and planted in well-drained soil during the growing season. The bulbs can be planted at a depth of 5 cm, and the rows should be spaced 20 cm apart. Vegetative propagation is a common method for commercial onion farming, and it ensures that the desirable characteristics of the parent plant are passed to the offspring.
Sexual Propagation
This method involves the use of seeds. The seeds can be obtained from mature flowers that are allowed to go to seed. The flowers are carefully collected and crushed to obtain the seeds. The seeds are then dried and stored in a cool, dry place. When planting the seeds, it is important to ensure that they are planted at a depth of 2 cm. The soil should be well-drained, and the seeds should be watered regularly. It is also important to ensure that the soil is free of weeds that can compete with the onion plant for nutrients and water.
Disease and Pest Management for Allium cepa L. var. viviparum M.C. Metz
Allium cepa L. var. viviparum M.C. Metz, also known as tree onion or Egyptian walking onion, is a hardy plant that is resistant to most pests and diseases. However, it is still possible for some pests and diseases to affect the plant.
Common Pests
One of the most common pests that affect the tree onion is the onion maggot. The maggot is a fly larva that burrows into the onion bulbs and feeds on them. To prevent infestations, it is necessary to rotate crops and avoid replanting onions in the same location.
Another pest that affects the tree onion is the thrip. Thrips are tiny insects that feed on the sap of the plant, causing the leaves to turn yellow and dry out. Pruning the affected leaves and keeping the plant well-watered can help control thrip infestations.
Common Diseases
One of the most common diseases that affect tree onions is white rot. White rot is a fungal disease that affects the roots and bulbs of the plant. The affected parts of the plant become soft and mushy, eventually leading to plant death. To prevent white rot, it is important to rotate crops, remove any infected plants, and improve soil drainage.
Another disease that affects tree onions is downy mildew. Downy mildew is a fungal disease that causes yellow spots on the leaves and a greyish-white coating on the underside of the leaves. To prevent downy mildew, it is important to water the plant from the bottom and avoid overhead watering.
Pest and Disease Management
Preventing pest and disease infestations is the best way to manage them. Crop rotation, good soil drainage, and removing infected plants are all important practices that can help prevent pest and disease infestations. For specific pest and disease infestations, there are various organic and chemical treatments available, but it is important to follow instructions carefully and avoid any potential harm to the plant or the environment.
