Typically, onions are planted early in the spring and harvested in the fall after their tops begin to die back. In the southern U. Add aged manure or compost to the soil in early spring, before planting. Onion seeds are short-lived.
Onions contribute savoury flavour to dishes without contributing significant caloric content. Allergic reactions may not occur when eating cooked onions, possibly due to the denaturing of the proteins from cooking.
Freshly cut onions often cause a stinging sensation in the eyes of people nearby, and often uncontrollable tears. This is caused by the release of a volatile gas, syn-propanethial-S-oxidewhich stimulates nerves in the eye.
These break down amino acid sulfoxides and generate sulfenic acids. A specific sulfenic acid, 1-propenesulfenic acid, is rapidly acted on by a second enzyme, the lacrimatory factor synthase, producing the syn-propanethial-S-oxide.
Lacrimal glands produce tears to dilute and flush out the irritant. The more often one chops onions, the less one experiences eye irritation. Inthe New Zealand Institute for Crop and Food Research created "no tears" onions by genetic modification to prevent the synthesis of lachrymatory factor synthase in onions.
Sandy loams are good as they are low in sulphur, while clayey soils usually have a high sulphur content and produce pungent bulbs. Onions require a high level of nutrients in the soil.
Phosphorus is often present in sufficient quantities, but may be applied before planting because of its low level of availability in cold soils. Nitrogen and potash can be applied at regular intervals during the growing season, the last application of nitrogen being at least four weeks before harvesting.
Most traditional European onions are referred to as "long-day" onions, producing bulbs only after 14 hours or more of daylight occurs. Southern European and North African varieties are often known as "intermediate-day" types, requiring only 12—13 hours of daylight to stimulate bulb formation.
Finally, "short-day" onions, which have been developed in more recent times, are planted in mild-winter areas in the autumn and form bulbs in the early spring, and require only 11—12 hours of daylight to stimulate bulb formation.
Onion seeds are short-lived and fresh seeds germinate better. In suitable climates, certain cultivars can be sown in late summer and autumn to overwinter in the ground and produce early crops the following year. These bulbs are planted the following spring and grow into mature bulbs later in the year.
The plants are shallow-rooted and do not need a great deal of water when established. Bulbing usually takes place after 12 to 18 weeks.
The bulbs can be gathered when needed to eat fresh, but if they will be kept in storage, they should be harvested after the leaves have died back naturally.
In dry weather, they can be left on the surface of the soil for a few days to dry out properly, then they can be placed in nets, roped into strings, or laid in layers in shallow boxes. They should be stored in a well-ventilated, cool place such as a shed.
The most serious for the home gardener are likely to be the onion fly, stem and bulb eelworm, white rot, and neck rot. Diseases affecting the foliage include rust and smut, downy mildew, and white tip disease.
The bulbs may be affected by splitting, white rot, and neck rot. Shanking is a condition in which the central leaves turn yellow and the inner part of the bulb collapses into an unpleasant-smelling slime.
Most of these disorders are best treated by removing and burning affected plants. The fly is attracted to the crop by the smell of damaged tissue and is liable to occur after thinning. Plants grown from sets are less prone to attack. The larvae tunnel into the bulbs and the foliage wilts and turns yellow.
The bulbs are disfigured and rot, especially in wet weather. Control measures may include crop rotation, the use of seed dressings, early sowing or planting, and the removal of infested plants.
Young plants are killed and older ones produce soft bulbs. No cure is known and affected plants should be uprooted and burned. The site should not be used for growing onions again for several years and should also be avoided for growing carrotsparsnipsand beanswhich are also susceptible to the eelworm.
As the roots rot, the foliage turns yellow and wilts. The bases of the bulbs are attacked and become covered by a fluffy white mass of myceliawhich later produces small, globular black structures called sclerotia.
These resting structures remain in the soil to reinfect a future crop. No cure for this fungal disease exists, so affected plants should be removed and destroyed and the ground used for unrelated crops in subsequent years.
It is caused by Botrytis alliiwhich attacks the neck and upper parts of the bulb, causing a grey mould to develop. The symptoms often first occur where the bulb has been damaged and spread downwards in the affected scales. Large quantities of spores are produced and crust-like sclerotia may also develop.
In time, a dry rot sets in and the bulb becomes a dry, mummified structure.Typically, onions are planted early in the spring and harvested in the fall after their tops begin to die back.
In the southern U.S., some onion varieties can be planting in the fall. Health Benefits of Onions. Onions are rich in sulfur-containing compounds that are responsible for their strong lausannecongress2018.com is a powerful detox element and helps the body to release toxins, especially for the lausannecongress2018.com naturally high in sulfur also help the body to detox from heavy metals like lead, arsenic and cadmium..
The onion is the richest dietary source of quercitin, a powerful. Allium canadense: The Stinking Rose. Your nose will definitely help you confirm that you have found wild onions, Allium canadense, AL-ee-um lausannecongress2018.com called Wild Garlic and Meadow Garlic by the USDA, walking through a patch raises a familiar aroma which brings me to a foraging maxim.
Jun 09, · Other familiar alliums, like elephant garlic, ordinary chives, wild ramps and ramson, generate variable mixtures of the garlic, Chinese chive and onion weapons, and have a blend of their flavors.
Many people have trouble digesting onions, especially when eaten raw. Some people belch, develop gastroesophageal reflux, have abdominal pain and bloating, constipation, diarrhea, or feel as if their meal is sitting in their stomach for longer than usual.
Onions are a staple in any well-stocked kitchen. Served raw, they add a crisp bite to salads and burgers, and when cooked they add a pungent, lightly spicy flavor that complements almost any savory dish--they can even be caramelized to sweetness!
Onions are a member of the allium family of plants.