Onion - all articles

Planting density is a very important management factor in determining bulb size in onion crops. In addition, good crop nutrition can help growers to achieve a desired diameter. Nitrogen, potassium and phosphorus are essential to influence onion bulb size.

A balanced crop nutrition program can help to improve overall yield by increasing onion bulb weight.

The number of onions produced can be influenced by a variety of factors, for example, plant density. Planting crops at higher densities can result in greater numbers of onion bulbs, but of smaller size. Thus, it is important to manipulate sowing density to provide maximum yields of a desired bulb size. A balanced fertilization program will help to reach yield potentials.

The majority of onion crops are grown for the fresh market. Bulbs should be sufficiently dry for the intended purpose. Most common bulb onions have 10-12% dry matter. Onions grown for dehydration require higher dry matters of 17-20%. Nitrogen and potassium are the most important nutrients influencing dry matter content of onion bulbs.

Firmness is a critical characteristic of onion crops, particularly in dry bulb onions which are stored for long periods. Growers can influence bulb firmness by applying balanced nutrition.

Taste and pungency of onions are key quality characteristics of this crop. They vary among types and cultivars. Pungency is largely due to the level of sulfur - based non-protein amino acids they contain. Sweetness can be assessed by the levels of sugars in the bulb. Although measurement of these elements can be difficult, it is well known that good nutrition is essential to managing taste and pungency of onion bulbs.

A uniform skin is a major element of onion appearance for the fresh market. In addition, the strength of the onion skin is important to help keep diseases and storage problems away. Skin cracking can be a result of poor soil moisture. A balanced nutrition program is also essential to ensure that the overall skin quality of an onion crop meets market demands.

Onions should be mature and dry when harvested. Onion bulbs need to be carefully handled to minimize bruising and cuts that can allow disease to enter. Onions need a period of curing or drying in order to seal the neck, prevent invasion of diseases and rot and to create a bright, crack-free skin. In temperate regions, curing is usually carried out in storage, but elsewhere, onions are lifted and left to dry in the field.

Onions thrive best when temperatures are cool during early development and then warmer and sunny during maturity. Nutrition programs containing soluble calcium can help to protect crops against chilling injury, which can lead to cell breakdown.

It is particularly important to ensure that environmental and growth constraints do not limit bulb formation and bulb quality.

Onions can often lose weight when stored for a long time. Sprouting and rot can also occur. The crop should be carefully dried in the field before storage to minimize rot. Controlled atmosphere storage is increasingly practiced to maintain quality over longer periods and extend the marketing period. Appropriate crop nutrition can help to maintain the storage quality of crops.

Your onion crop require the right nutrients, at the right time, to achieve the best results possible. Here you find an overview of the role of nutrients by onion growth stage.

Onions are widely grown across a range of climates but thrive best when temperatures are cool during early development and then warmer and sunny during maturity.

Yara's crop nutrition program for onions can help you to achieve excellent crop performance and maximize the yield and quality of onion crops.