IT MIGHT seem a bit chancy at the moment, but the late drilling window still open – of you choose the right variety.

For those who are late-drilling wheat after potatoes, or those forced into this due to the weather, it’s important to consider the specific challenges this poses to the crop, pointed out Limagrain UK’s arable technical manager, Ron Granger.

“Delayed or late drilling of winter wheat, considered to occur from mid-October onwards, is common practice on some farms these days. However, as autumn progresses and soils inevitably become cooler and wetter, it is important to make a distinction by choosing varieties that will cope well, rather than be challenged by the situation,” he said.

“Get it wrong, and you could be facing fairly substantial yield penalties – but this is totally avoidable. Crops drilled later will not be in the ground as long as those drilled earlier in the autumn, so the chosen variety needs to establish well and once growing conditions are favourable in the spring, needs to be quick off the blocks.”

Characteristics of wheats that suit the late drilling slot are strong and vigorous tillering, combined with good rooting plus a semi-prostrate growth habit in the winter, said Mr Granger. “This is especially important where black-grass is present, as you need a variety that will compete with its rapid growth rather than sit and tiller flat to the ground where it may eventually become smothered by the black-grass.

“The theory is not complicated and this is why certain varieties like LG Skyscraper suit the black-grass situation,” he said, adding that Limagrain carries out trials looking at which varieties better suit the later-drilled slot. “This is valuable information for growers, especially when also considering limited AHDB data sets.”

In Limagrain’s 2019 trials, LG Skyscraper – the highest yielder on the 2019/20 AHDB Recommended List – outperformed all others this year and was the highest performing variety in the late drilled test. In fact, it took pole position over three very different seasons, he pointed out.

Another option is Group 2’s LG Detroit. “The significant thing about it is that it is stiff strawed and comes with orange wheat blossom midge (OWBM) resistance. The added value characters of high inherent protein content, from its parent Crusoe, and good fusarium resistance are also valuable assets for a quality wheat,” said Mr Granger.

“Our agronomy work suggests that LG Detroit benefits from a higher seed rate if sown later in the season, as the variety does tend to drop tillers in the spring if in a stress situation, in a drought scenario.”

Mr Granger highlighted data from several seasons of work from Limagrain, that suggested that taller wheats, such as LG Skyscraper, are at an advantage in the later drilling scenario, because larger plant canopies also play an important role in keeping black-grass ear numbers and seed return to the minimum.

One of the single most important factors in getting a late drilled crop off to a good start is to use the correct seed rate.

“Seed rates after the end of October are difficult to quantify specifically, as they will be more determined by the seasonal weather and seedbed preparation, at the time of drilling,” he said.

“Generally, seed rates should be increased the further drilling moves towards the winter months, to compensate for the impact on tillering, as a result of cooler temperatures and shorter days. In good conditions in early November, the target should be a seed rate of 375-400 seeds/m2, increasing to 400-475 seeds/m2 at later drill dates, or in a black-grass or poor seedbed situation.”