How to Control Weeds Effectively

Weeds compete with your crop for water, nutrients and light. In maize, uncontrolled weeds in the first 6 weeks can cut yield by up to 50%. Hand weeding works, but on anything bigger than half an acre, herbicides save time, money and your back.

Pre-emergence: stop weeds before they start

Spray within 3 days of planting, on moist soil, before the maize and weeds emerge. Products like Bullet (acetochlor + atrazine) or Lumax form a film on the soil surface that kills germinating weed seeds. Use a flat-fan nozzle and walk at a steady pace — overlapping or skipping strips creates weedy patches.

Post-emergence: clean up what got through

When the maize is 4–6 leaves and weeds are small (2–4 leaves), spray a selective post-emergence herbicide such as 2,4-D Amine for broadleaf weeds, or a nicosulfuron-based product for grasses like couch and wild oats. Always check the label for the maize growth stage — spraying too late burns the crop.

Spraying tips that actually matter

Spray in the morning or late afternoon when wind is low. Use clean water — muddy water blocks nozzles and reduces effectiveness. Calibrate your knapsack: 200 litres of spray solution per acre is the standard. Always wear gloves, a mask and long sleeves.

Talk to us about Roundup, Bullet, 2,4-D, Touchdown Forte and a full range of selective herbicides. We also stock knapsack sprayers, nozzles and PPE.