The results of a new survey of maize growers have revealed valuable crop knowledge that can be shared to help farmers get the most from their harvest.
Nearly 100 producers, totaling approximately 24,000 dairy and cattle animals, participated in the survey.
It was the first to be carried out by the Maize Growers Association (MGA), the British Grassland Society and forage specialist Grainseed since 2016.
See also: Tips on growing maize under film, plus costs
The survey showed that the area devoted to maize on each farm has increased by 53% over the past five years, from an average of 43 ha (107 acres) to 62 ha (153 acres) in 2021.
In previous surveys, the main reason given for growing maize was to increase the energy of livestock rations, says Neil Groom of Grainseed.
This time it was crop reliability and better use of farmyard manure and slurry.
While the area planted to corn has increased, 24% of respondents said they were growing less grass than five years ago, he says.
“There are obviously more people growing corn for anaerobic digesters (AD) and that needs to be taken into account.
“But the general trend is that farmers are relying more on maize after very difficult seasons for grass growth and silage.
Below, MGA’s Jon Myhill talks about some of the key findings and offers management tips and advice for making the most of the UK’s expanding maize area.
1. Properly prepare seedbeds
Results: 69% of growers say tillage followed by weeding is their preferred method of seedbed preparation, and only 8% use minimum tillage. More than half (52%) of producers regularly subsoil to reduce compaction.
- An open, free-draining soil structure is essential
- Before a new season, check the compaction. Corn is a “lazy-rooting” crop, so any signs of compaction should be alleviated with a plow, subsoiler, or even a shallow tine. On the other hand, if you don’t have compaction, entering with a subsoiler can be a wasteful pass.
- Good seed-to-soil contact is crucial; however, optimum seedbed conditions change depending on when the corn is planted, the type of soil it is planted in, and weather conditions at the time of planting. Many growers create a finer seedbed than necessary
- A rough seedbed may be best in the beginning (mid-April) during a colder season. Looser, rougher ground will warm up faster when temperatures start to rise
- Later in the season, when temperatures are higher, finer plowing will allow for better moisture retention and heat unit absorption for faster germination.
- Before drilling, make sure you know where the moisture is in the ground. The last thing you want to do is break through some wet areas and some dry areas, as this will lead to staggered germination and uneven crops at harvest time.
2. Optimize the use of farmyard manure (FYM) and slurry
Results: 52% of producers say better use of FYM/slurry is the biggest benefit of corn.
- Organic manure is particularly useful for maize. It’s a hungry crop that needs lots of good nutrition – especially fresh potash and phosphate to start germination.
- If you are using FYM cattle or slurry, an analysis is essential to know exactly which nutrients you are applying or not.
- A soil test is also important to understand your soil indices
- In addition to cultivation, organic fertilizer can also benefit soil structure and moisture retention
- For best results, manures should be incorporated into the soil within 24 hours of application to minimize losses.
- MGA nitrogen curve trials have shown that while the max N level in maize is 150 kg/ha, similar yields are possible using rates of 75-100 kg/ha if there is had historical use of organic manure, or if corn was grown after a cover crop.
- With artificial fertilizer prices high this season, be realistic about your expected yield potential. If you’re historically getting low yields, full nitrogen rates probably aren’t necessary.
- There is also a lower carbon footprint where fewer artificial sources are used.
3. Use Starter Fertilizer Wisely
Results: 67% of producers always use a starter fertilizer, and an additional 7% say they use one sometimes.
- Most corn crops will benefit from a small amount of starter fertilizer at the seeding point to promote efficient germination
- Be aware of soil index before applying. Remember that if your phosphorus index is 4 or higher, you can no longer apply phosphate to that field.
- Biostimulants can help release phosphate. While MGA trials did not specifically show a yield advantage when biostimulants were used, we did see an improvement in metabolizable energy (ME) and starch content of the crop.
4. Consider starting cultures under film
Results: The number of farmers growing maize under film increased to 12% in 2021 – from 6% in 2016.
- Growing under film creates more heat units for plants and provides a microclimate to enable successful germination
- This expands the geographical potential of maize, which means growers in non-traditional areas, such as the North, can achieve good results from the crop.
- To justify the additional cost, it is important to have a good seedbed, because the film must be buried in the ground at the edge of each row.
- The best results will also come from selecting varieties suitable for growing under film.
- Starch-based films without plastic content are developed with environmental concerns in mind.
5. Mitigate summer droughts
Results: Of the 52% of growers saying climate change is a key management issue, 62% said summer droughts are their biggest problem.
- Analysis of Met Office weather data over the past five years has shown a trend towards warmer and wetter winters, combined with prolonged summer droughts
- On dry soils, is it worth keeping seeding rates at 85,000-95,000 seeds/ha
- The use of FYM and slurry, along with good tillage and rolling immediately after sowing, will help retain soil moisture. If you are on drought prone land, consider applying more FYM/slurry
- If you are in an area with traditionally low rainfall, look for varieties that have proven higher levels of drought tolerance.
- Yields can be higher where maize is irrigated, but this can be costly.
6. Make better use of cover crops
Results: Growing cover crops is a post-harvest management practice for 28% of farmers.
- Cover crops are valuable from an environmental perspective, but also help condition the soil before the corn
- Depending on the mix of species used, subsequent crops may also benefit from greater availability of nitrogen and other key nutrients
- Cover crops provide an additional source of income via overwintering cattle or sheep
- A three-way mix including nitrogen-fixing species such as vetch or clover works well for corn. Besides that, it is important to have a good soil cover, provided by oats or rye for example. Phacelia and radish are also useful additions
- Cover crops should be planted as early as possible to avoid soil moisture loss after the combine.