Potassium is a vital nutrient for maize production second to nitrogen in terms of quantity of a maize plant’s needs. Its deficiency is first seen on young lower leaves which are green and turn yellow and brown. This may progress to upper leaves. Curling leaves with inter-veinal scorching and necrosis. Cobs of plants which have been deficient of potassium are noticeably narrowed or peaks and the grains on the cobs will have been poorly filled.
Potassium is important for healthy green foliage and ensures optimal root growth which contributes towards increased yields. It supports water uptake in the plant when water is not readily available. It also regulates plants leaf tissue openings, thus reducing water loss through the leaves. Activates enzymes required for growth.
Potassium deficiency can be managed by applying the following:
- Apply manure at the rate 1000 kg/Ha to improve water holding capacity and minimize leaching of nutrients from the soil
- Do not allow the ground to become waterlogged
- Keep fields free of weeds
- Avoid burning crop residue on the land after harvest so that nutrients from the residues can enter back into the soil
- Apply inorganic fertilizers such as 23:10:5+6S+1.0Zn at the rate of 100 kg/Ha using a bottle top of a 300 ml glass Fanta bottle with lining inside at 10 cm away from the planting station and 10 cm deep with planting stations spaced at 25 cm apart (one-one planting pattern).