By large, it forms part of food security as it is a source of nutrients required by the human body. Bulb onion contains antioxidants which keep lifestyle-related diseases in check, and thus it is a vital component of a balanced diet. In addition to being consumed as a vegetable, onions also have medicinal values. Onion ( Allium cepa L.) belongs to the Alliaceae family and is a valuable vegetable crop worldwide. The study recommends harvesting of onions at 75% top fall and curing for at least one week before topping for enhanced visual and keeping quality of harvested bulb onions. Although seasonal variations were significant for some of the parameters assessed, a similar trend was observed in both seasons. Bulbs that were harvested at 75% top fall and cured for one or two weeks before topping were found to have significantly better visual and keeping quality.
After three months of storage, the bulbs were assessed for visual and keeping quality using incidences of skin rots, skin colour, percent of marketable bulbs, residual weight of the bulbs after curing, and days to 50% sprouting. The treatments consisted of harvesting stage (25%, 50%, and 75% top fall), curing period (none, 1 week, and 2 weeks) and time of topping (before and after curing). The experimental design was a split-split plot laid out in 3 × 3 × 2 factorial arrangement. The study was carried out in Yatta Sub-County, Machakos County, Kenya. This study evaluated the combined effects of harvesting stage, curing period, and time of topping on postharvest visual and keeping quality of red bulb onions. Most postharvest strategies applicable to onions are applied singularly, and therefore, their combined effects have not been well studied. ) in Kenya is constrained by postharvest losses.