Although early maturing varieties will be ready for harvest around 20 days earlier than later maturing alternatives, the agronomy of the crop will be very similar according to Richard Camplin of Limagrain UK, who points out that maturity class mainly influences what happens at the end of the growing season.
“The key to a good crop, irrespective of the variety is ensuring good establishment,” he comments. “This, combined with selecting a variety with good early vigour will ensure plants develop a good root system and achieve good leaf cover which is essential to optimise photosynthesis.”
Mr Camplin says that management must be focussed on achieving good germination and getting the crop away to a strong start. He explains that irrespective of variety there is a period of around 90-100 days between germination and flowering. It is during this time that the plants puts on all its vegetative growth.
“Once the plant has flowered it stops creating vegetative material and solely develops the cob. As the vegetative portion of the plant provides half the energy of the eventual crop, it is important to maximise this growth, especially if the variety has high digestible NDF which means more of this energy will be utilised when fed.
“What you need to avoid is the plant germinating and then sulking because of poor seed bed or low soil temperatures. All this does is create a period in the crucial phase between germination and flowering when the opportunity for vegetative growth is lost.”
Mr Camplin advises ensuring fields for maize are not suffering from compaction, explaining that as maize is a deep rooted plant any compaction will reduce the plants ability to reach water and nutrients, which can stress the crop delaying maturing and reducing yield.
He advises leaving final seed bed preparation, when the top 5cm is worked to a fine tilth, until immediately prior to drilling to preserve soil moisture.
“Soil moisture is important but the key measurement is soil temperature Cold soils are the enemy of strong establishment. Avoid drilling before soil temperatures have achieved a minimum of 8°C and have been rising for at least four days. For heavier soils, wait until they are 12°C. A soil thermometer is a sensible investment.
“Drilling into colder soils just reduces the extent and rate of germination. If in doubt delay drilling as the few days apparently lost will soon be recovered if plants get away quicker. Late frosts and heavy rain will both drop soil temperature.
“Drilling early varieties into warm soils will ensure they have the best chance of getting away strongly, maximising vegetative growth and helping ensure a good yield of quality forage while allowing successor crops to be established in good time.”