Onions are an irreplaceable crop, without which no vegetable garden can do. For example, yellowing.
If this happens in August-September, then no one is definitely worried. This is just a sign of ripe bulbs that are about to be pulled out of the ground. But why does the onion turn yellow when it is still growing and growing? There may be several reasons. Perhaps pests, or rather the onion fly, are to blame. Its larvae settle in the bulb and liquefy it. As a result, the feather turns yellow and withers. It is not difficult to find this parasite. Fleeing from flies, gardeners alternate planting onions, place beds near carrots, water the plants with a solution of table salt (half a glass per 10 liters of water). There are also special preparations that repel this insect.
Another reason is the lack of nitrogen in the soil. This happens if there is not enough moisture or after heavy rains, when nitrogen along with water goes deeper into the ground. In this case, you should resort to fertilizers containing this trace element. For example, urea or manure infusion or other complex remedy.
Onions are also very fond of loose soil, rare and abundant watering. An excess of moisture is fraught with phytoepidemia. Better not to rush, 4-6 times a month is enough. This popular culture can also have other diseases, fungi, rot, etc. Almost all disturbances in normal growth are accompanied by yellowing of the feathers.