Safe herbicide for weeds in my onion crop?

Onion is a slow-growing, shallow-rooted crop with thin leaves, so it competes poorly with weeds and weeding cost is a real burden, but there are herbicides registered for onion that, used correctly, are safe and cut labour a lot. A common approach is a pre-emergence spray such as pendimethalin applied a few days after transplanting (or after sowing in direct-sown onion) on a moist, well-prepared bed, which controls the early flush of grasses and many broadleaf weeds. A post-emergence grass killer such as quizalofop can be used later to clear grassy weeds without harming the onion. Oxyfluorfen is also registered for onion in some recommendations but is sensitive to dose and stage, so it must be used exactly per label or it can scorch the crop. Spray on a moist field with weeds small, using the full label water volume and a flat-fan nozzle, and avoid spraying in very hot midday conditions. One hand weeding is still often needed around 40 to 50 days. Use only herbicides registered for onion, follow the product label dose and timing exactly, and confirm with your local KVK, because onion is sensitive and the wrong herbicide or dose can damage the crop.