Carlisle maize trials target ways of maximizing maize production

More than 60 maize growers and contractors from across the northwest had an insight into the latest varieties and growing techniques when Hutchinsons opened the doors to its Carlisle Maize Regional Technology Centre in Cumbria in September.

It is the 13th year that Smalmstown Farm has hosted the maize trials, kindly hosted by Mr & Mrs R Fisher, which are tailored to finding new ways of maximising the output of maize grown under film and open ground in the more marginal growing conditions often experienced in northern and western parts of the country.

"Although conditions have generally been pretty good this year, our climate in this area can be less conducive to warm-season crops," explains Hutchinsons agronomist Jim Clark.

"Up here, many growers establish maize under film to mitigate some of the early season risks from cooler temperatures in spring, but the technique creates its own challenges and requires considerable investment, so maximising crop output is vital to secure the future of maize growing in such areas."

Mr Clark expected the Carlisle maize plots to be harvested around the end of September into early October and said yield and quality results would then be analysed over the autumn.

Variety plots

With over 17 varieties on display both under film and in the open, visitors to the trials day had plenty of opportunity to look at the performance of established and new varieties showcasing a range of early to late maturities.

 The trials demonstrated the latest varieties under film from a range of leading plant breeders such as Germinal, Corteva, Bayer, Limagrain, RAGT and Elsoms whilst the open plot varieties demonstrated the latest varieties from Limagrain, RAGT and Pioneer.

"It's been quite clear this year that some varieties have really stood out, so it will be worth discussing these before making decisions about what to grow next year," says Mr Clark.

The biggest variety up here for Hutchinsons continues to be P7034 from Corteva (Pioneer)," says Mr Clark. "It is a consistently good all-rounder and has the dent-type grain that has been bred specifically for the cooler maritime locations found here in the UK.  It also delivers a good fresh and dry weight yield with high starch levels that are more rumen-degradable and allow shorter clamp to feeding time."

"There are some newer varieties of interest; P7179 is a new open or under film early variety from Corteva that is currently registered in Europe, that should be available in the UK next year. Bayer's DKC 3218 shows appeal as an early driller, it's a big plant type, big cob and early to mature."

"Germinal's variety Cardif is an early alternative which is extremely vigorous at peri-emergence, and produces a bigger plant with good cobs and early maturity which has always been in our top three performers in the Carlisle trials and is exclusive to Hutchinsons in the north of England."

Narrow film discussion

One feature that generated particular interest among visitors to the event on 16 September was the trial of crops established under a new narrow-row version of a 100%  starch-based film, Samco Bio, that is now in use across Europe.

Whilst the maize plants physically liked being grown under this film, with an upfront cost of around 20% more than conventional wide row film, Mr Clark acknowledged that the system was more expensive, but pointed out that whilst the UK was not obliged to use the film currently, it was interesting to see how the maize crop performed under it. 

"If we were to find ourselves where starch-based films become standard as is the case in Europe, at least we are one step ahead and have tried and tested it in advance and will continue to test new growing techniques."

Nutritional boost

Starter fertilsers continue to show a benefit; for the third year running in trials, plots of P7034 were sown on 10 April under Samco Oxo Bio film using a specially modified drill fitted with a micro granule applicator. The starter fertilisers compared were the ammonium phosphate-based Primary-P and Biolite.

"We'll know more once crops have been harvested and yields analysed, but so far we're definitely seeing similar results in terms of crop development to last year, when plots that received the starter fertiliser established quickly and looked physically bigger than untreated maize."

"Starter fertilisers could also negate the risk of root scorch occurring when granular fertiliser is applied "down the spout" and sits too close to the seed. It is a particular risk in rough, dry seedbeds where fertiliser does not dissolve, so scorches developing roots," he says.

"We are also seeing really positive results with crops maturing as much as a week early, where late applications of liquid release nitrogen Ndurance, is applied at the 8-10 leaf stage usually about the end of June/beginning of July which has become common practice on most maize grown in Cumbria and SW Scotland."

Undersowing work in progress

Another popular talking point was the trial looking at undersowing maize with grass to reduce erosion and build soil health. The technique is increasingly popular, as farmers are more reluctant to leave soils bare over winter and also recognize the value of additional grazing it offers.

Mr Clark pointed out that we have learnt much about undersowing over the last few years and offered his top tips for undersowing success:

1. If undersowing for grazing, the best grass for this is the Westerwold Italian ryegrass mix between the maize rows at 6-9 kg/acre eight weeks after drilling.
2. If undersowing for soil health benefits and to prevent erosion, use fescue or amenity grasses as they have good deep rooting and also shallow surface rooting to hold onto the soil. The seed rate can be lowered to 4-kg/acre.
3. Always drill into moisture.
4. Broadcasting or drilling both work, as long as there is sufficient moisture in the soil.
5. Consider the longer term impact from sulfonylurea herbicides  which could adversely affect grass establishment. If applied pre-emergence, too close to the emerging crop, there can be an impact on the crop, as the half life of the residual continues to work. This is particularly the case if its dry at application, and then it rains later on, as the moisture activates the residual.

Order seed early

Demand for maize seed in the UK has continued at an all time high for the last few years and is likely to remain so for 2022/23. Seed production instability and logistical challenges remain a feature looking ahead and seed supply will be tight. So, the advice is to order early this year, particularly if after a certain variety.