Forage maize struggled to make the grade on many UK units in 2022. So what steps can growers take this spring to help ensure 2023’s crop is a success?
TEXT PAUL JENNINGS
Testing weather conditions in 2022 brought into sharp focus the challenges maize growers can face when trying to produce a high-yielding, nutritionally valuable crop. Dry and hot conditions resulted in many crops underperforming and even failing. So how can producers mitigate the effects of variable weather patterns, disease and pest-related stresses?
According to Limagrain’s Tim Richmond, key factors to consider when planning for a successful maize crop are varietal agronomics, drilling depth and seedbed conditions, as well as minimising the threat from pests, disease and birds, and ensuring the crop matures early enough to allow timely harvest without risking excessive soil compaction, erosion or run-off.“
With weather patterns becoming increasingly volatile and difficult to predict, it is more important than ever to plan carefully for the season ahead to ensure maize crops stand the best chance of achieving their true potential in terms of yield and energy content,” he explains.
“What 2022’s excessively hot and arid conditions highlighted is that it’s crucial to get crops off to a strong start, so they are better able to cope with stress later in the season. Growers should select the most appropriate variety for their specific location, and preferably one which has been tested and proven in UK conditions.”
He adds that factors including available heat (measured in Ontario heat units) and average rainfall will dictate whether a ‘very early’ variety such as Prospect, an ‘early’ variety such as Saxon, or an ‘intermediate’ maturing variety such as LG31207 should be grown.“
That’s as true for maize grown for ensiling as it is for crimped or grain maize, and for crops destined for biogas production. But there’s never any guarantee the season will pan out as expected. So to give the selected variety the best start, additional care is required at drilling and during the establishment phase.”
Mr Richmond says drilling should only start once soil temperature has reached 10 degrees C for at least four consecutive days, and when the medium-term forecast looks favourable. “This will ensure seed germinates quickly and plants grow away strongly. Crops should also be drilled into well-aerated soils because maize won’t thrive in compacted soils where oxygen is limited. A starter fertiliser, applied with the seed at drilling, will also help the crop to grow away quickly.”
How crops coped during 2022’s drought came down to how they fared during the establishment phase, according to Mr Richmond.
“Crops drilled into a warm, well-aerated seedbed with a decent amount of retained moisture rapidly put down strong roots. This meant they could cope with the ensuing dry conditions and developed an early canopy, which helped to out-compete and suppress weeds. “In contrast, crops that went into drier ground, either as a result of poor timing, lack of rainfall or where heavy cultivation had caused excessive moisture losses, failed to put down a decent root and suffered more as the dry conditions took hold.”
In terms of specific agronomic traits, he recommends not only looking at the usual performance indicators, such as dry matter yield and starch content, but also at additional factors including early vigour, lodging ratings, disease resistance, and maturity classification. “Irrespective of the crop’s end use, there’s no point chasing outright yield if the crop doesn’t contain enough metabolisable energy or if it grows too tall for its root structure and ends up lodging,” he says. “A variety that puts down strong roots stands a better chance of remaining upright, and will also be able to grow away more quickly and withstand dry conditions for longer due to its ability to scavenge water and nutrients from depth.
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“Likewise, a crop with natural resistance to diseases, such as stalk rot, will also be easier to grow, although it will still pay to manage disease carefully, particularly if the season turns out to be less than ideal.
”Matford Arable’s Neil Potts agrees, adding that cool and humid conditions will aggravate the threat of disease. “Fortunately the cool, damp conditions that can exacerbate diseases have been relatively uncommon in recent years but it still pays to be aware of the risk, particularly because fusarium can be tricky to control once it has taken hold.“
It makes sense to thoroughly bury the previous crop’s stubbles and debris to help prevent diseases from over-wintering, and to have plans in place should a fungicide application be required.” The recent drive to reduce costs has resulted in a small but significant groundswell towards establishing maize either via direct drilling or minimum tillage.
In a favourable year these techniques work reasonably well, although the resulting crops can be a little smaller than their conventional counterparts,” says Mr Potts. “But it’s worth noting that 2022’s conditions proved too much for reduced tillage crops in the driest parts of the UK, which struggled due to their less-developed root systems and because many of the drills used didn’t have the ability to apply a seedbed fertiliser.”
Seed treatments and biological growth enhancers can also help to mitigate the effects of a poor season. “With feed prices remaining high, the value of home-grown forage has also increased,” Mr Richmond continues. “So it pays to protect crops from the outset with seed treatments, such as Korit Pro. As well as repelling birds and protecting against damping-off diseases, such as pythium, it also provides manganese and zinc to improve crop emergence and establishment through the susceptible two-to-six-leaf period. It also contains a plant-growth-promoting rhizobacteria (PGPR), which colonises the rootzone and aids nutrient uptake, and gives plants a healthier start.
“Ultimately, the key factor affecting how a crop performs at harvest is how well it was managed in its infancy,” Mr Richmond stresses. “Producers must do everything possible to get crops off to a vigorous start so that they stand a better chance of coping with whatever the season might subsequently throw at them.”