Autumn topdressing techniques for Welsh onions: master the timing and methods to boost yield

The Welsh onion is a vegetable that loves fertilizer. For a long time, many vegetable growers have been accustomed to digging trenches to apply all the topdressing to Welsh onions in one go, but this is not scientific. This is because doing so not only easily cuts the roots and root hairs of the Welsh onion, but also, because the fertilizer is applied too concentrically, burns the young tender root hairs of the Welsh onion, leading to dry tips and withered leaves, affecting the quality of the Welsh onion and reducing yield. Therefore, trench topdressing is definitely not the way to go.

The correct fertilization method should be: follow the principle of "small meals, more often," adopt the method of earthing up to cover the fertilizer, and apply topdressing 3~4 times from transplanting to harvest, to prevent fertilizer shortage in the later stage of Welsh onion growth. Each time, apply 20~30 kg of ternary compound fertilizer per mu, or 10~15 kg each of urea and potassium sulfate; according to the growth stage of the Welsh onion, each topdressing amount should be slightly more than the previous one; when topdressing, evenly broadcast the fertilizer on the soil surface around the roots of the Welsh onion, then earth up to cover the fertilizer, reducing fertilizer volatilization losses, promoting the softening and elongation of the white stalk, and enhancing wind resistance. Within two days after earthing up and fertilizing, water once, so that the fertilizer dissolves into the soil and decomposes quickly, promoting the growth and development of the Welsh onion. (Wang Deming)