Forage maize can be tricky to establish and the often dry conditions in late spring do not help. This crop can produce up to 50 t/ha of fresh weight in just 4 months and its root system must be able to support the nutrient demands for this growth.
Foliar phosphate promotes better root systems
Early growth is predominantly root development which may be restricted in dry, cold soils if moisture is limited or conversely in poorly aerated cold waterlogged soils. Nutrient availability will be also be restricted in dry soils which will further restrict root growth and the ability to support the crop later in the season.
Foliar application of phosphate is the best way to overcome these early deficiencies and will help the crop develop a better root system to support later growth.
Research has shown that phosphate deficient maize plants growing in cold and/or acid soils utilise phosphate applied to the leaf at twice the rate of control plants without any deficiency; much more phosphate was translocated from the leaf, particularly to the roots, which maximises early root development.
Many maize crops will receive high volumes of farm yard manure or slurry, for which it is vital to know the nutrient content to be able to do a correct nutrient budget and plan the crops inorganic fertiliser requirements. Nutrient values for manures can be highly variable so rather than using 'book' values consider a laboratory analysis to know the exact nutrient content
A 40 t/ha crop will remove between 145 and 160 kg N/ha, with a peak uptake of 210 kgN/ha. Applications of manure and inorganic N need to be tailored to satisfy this demand.
Two farm trials conducted in 2010, which was a good maize growing year, raised starch analysis by an average of 20.1% following one spray of YaraVita Maize Boost at the 4 to 6 leaf stage.
Micronutrient deficiencies are also seen in maize, especially where little or no organic manures are applied. Key ones to look for would be Zinc, Boron, Copper and Manganese. A foliar analysis should be carried out if unusual symptoms appear.
YaraVita Maize Boost applied at the 4-6 leaf stage supplies fast acting foliar phosphate together with useful amounts of zinc, magnesium and potash for efficient uptake through the leaf.
Maize can be given a further boost by applying YaraVita Safe-N 300 once the crop has reached 1 to 1.2m height. Thi helps maximise efficient leaf canopy development.
In recent trials the application of Maize Boost followed by Safe-N 300 at the above rates and timings gave an extra 10% in dry matter yield.
The following micronutrient formulations contain mixtures of the micronutrients which are typically deficient in forage maize. Applying these multi nutrient mixtures generally ensures no single micro nutrient deficiency is overlooked.
The latest grassland fertilser and nutrition advice from the Yara agronomists.