Once the maize crop is successfully in the clamp it can be tempting to sit back and think about a job well done. However leaving the fields as stubble over winter can lead to soil erosion or leaching which could otherwise be avoided. It could also mean missing out on opportunities to produce additional forage and boost soil health through use of cover or catch crops.
ForFarmers forage product manager Mel Digger advises getting land back into production as soon as possible.
“The risks of leaving bare soil over winter are well known and include potential soil erosion, run-off and nutrient leaching.” This is particularly pertinent if harvesting created any ruts or damage. “It’s really important to consider longer term soil health during harvest,” she says. “Reducing tyre pressure on harvesting machinery can help reduce compaction and damage.
“If your maize land is on a slope then it is always best to drive across the slope rather than up and down,” she adds.
Although a subsequent crop drilled late in the year will not grow as quickly as a spring sown one it can still be productive and worthwhile. “Yields from overwintered crops harvested before the next maize crop is drilled can be up to 8t DM/Ha. Even if this isn’t taken for forage it can provide valuable organic matter, increase the soil’s moisture retention and fertility.”
From an environmental perspective green cover crops over the winter also provide habitat for wildlife, she says.
Drilling as soon as possible after maize is harvested is advisable to help the crop get off to a good start before temperatures drop. “Choosing the right species and variety is key here,” says Mel.
Aggressive and fast-growing grass species are the best choice. “Ryegrass will establish well before the winter months. In particular we recommend Westerwolds which establish quickly even in lower temperatures. They are high yielding and therefore a useful feed source in March or can provide a first cut of silage in mid April.” The downside is that they are not the hardiest grass over winter, she adds.
“Italian ryegrass can offer better longevity,” she suggests. “It will give comparable yields to Westerwolds but can last for two years. Either of these can be used on their own or in a mixture. Drill or broadcast as soon as possible after maize is harvested – certainly before the middle of October.”
Forage rye is another robust option, says Mel. “It is really hardy and tolerant of frost so can be a good low-risk alternative. It is suitable for many soil types but not ideal for exposed or badly drained fields.” It can provide early season grazing for cows or be baled.
Alternatively, you could consider a green manure crop. “Take every opportunity to improve the general health and fertility of your soil,” says Mel. “Fodder radish, phacelia and vetch are all possibilities. There are also mixes available to bring benefits of several species. A popular combination is forage rye and vetch or fodder radish and mustard.”
Thinking ahead to 2023’s maize crops and undersowing is worth considering. “Wait until the maize crop has established and then drill the cover crop so that it isn’t competing with maize in its earliest stages,” says Mel. “Having the cover crop in place prior to harvest means no rushing to get drilled straight after harvest and helps maintain soil structure.”
For further information and advice on what to sow after maize contact your local ForFarmers forage specialist. If you’re planning on growing maize in 2023 speak to us about reserving your chosen variety.