With the winter wheat drilling window well and truly open, Heather Briggs gets expert advice for those planning to hang on a little longer before the drill starts moving.
While late drilling winter wheat can offer advantages, growers need to consider these alongside any pitfalls, according to NIAB cereal crop varieties specialist Clare Leaman.
On one hand, they can offer advantages such as reduced incidence of certain cereal diseases such as septoria tritici and eyespot and rust, but the downside is that the ground is colder, resulting in slower emergence and crops spend longer at each development stage.
With increasing interest in drilling later, varieties are available which offer good yield and quality despite later drilling, she says.
“It is better to choose varieties with the best track record for performing at this time; the Recommended List (RL) includes information on varieties which can be planted from November,” she advises.
Generally speaking, varieties with a high tillering capacity tend to work well in a late drilling slot.
Vigour, the crop’s ability to grow away quickly and pass through the development stages as quickly as possible, is important, as otherwise they can be vulnerable to other pests and diseases.
“If seed is left in cold, wet soil, it may struggle to emerge with some rotting underground,” she warns. This means the ability to be up and out as soon as possible is crucial.
When it comes to planting dates, growers should not be over-concerned about the calendar as soil conditions are more important, adds Mrs Leaman.
“Of course as autumn advances, the weather becomes less predictable, but nevertheless you should still wait, if possible, and go in when the soil is in the best possible condition.”
Seed rates should be adjusted upwards so losses in establishment due to later planting can be recovered. Moreover, choice of seed dressing should depend on local experience, bearing in mind the previous crop.
“Choosing the best drilling dates depends on getting the right balance of all the different factors.”
Careful consideration of which varieties are suitable for drilling from mid-October onwards is crucial, says Limagrain UK arable technical manager, Ron Granger.
“Most wheat varieties can be drilled in the late drilled situation but from experience and seasonal trials work there are varieties that will perform better than most in this testing situation.
“Get it wrong and you could be facing fairly substantial yield penalties, and this is totally avoidable.
“Late drilling presents a unique set of challenges to the crop; soils will inevitably become cooler and wetter as winter draws in, so it is important to proceed with care and consideration to get the crop well established.
“Consequently, late drilled crops will not have been in the ground as long as those drilled earlier in the autumn, so once growing conditions are favourable in the spring, it is important that the variety is quick off the blocks.
“Translated into varietal characteristics this means that late drilled wheats need to be strong tillering, with a semi prostrate growth habit in the winter and have a faster plant development in the spring,” he says.
When in a black-grass situation, the speed and vigour of the crop in the spring is very important as you need a variety that will compete with the black-grass when growing conditions become favourable in the early spring, he continues.
“Within the Limagrain portfolio of wheat varieties LG Skyscraper, Motown and Evolution do have these desirable characteristics of good tillering in the late autumn with a faster speed of growth in the spring.
“Data would also suggest that taller wheats are an advantage in the later drilling scenario with the benefit of larger plant canopies also playing an important role regarding keeping black-grass ear numbers and seed return to a minimum.”
LG Skyscraper has shown itself to be very consistent in this situation with very high yield potential in both seasons, adds Mr Granger.
He acknowledges that spring wheat varieties have a place in the rotation for late drilling, especially in a black-grass situation; however, the right winter wheat varieties can be drilled through to the end of January without significant yield penalties.
Late drilling varieties made a step change in tillering ability and overall performance, first with Robigus, and then Oakley, says KWS product development manager, John Miles.
Today’s varieties have to deal with a changing climate; KWS trials during the 1990s indicated the cross-over point for switching between winter and spring varieties was the end of October, but when these trials were re-run in 2012, November-drilled wheat also yielded well.
“This is good news as it shows that growers have the opportunity to wait a little longer to lift sugar beet for example, but also those wanting to delay drilling well into October to control problem weeds, so they can opt for the higher margins and then drill winter wheat.”
Mr Miles notes that many growers prefer to drill winter wheat rather than spring wheat, even when it is late, because the latter has limited herbicide options.
“If winter wheat makes better agronomic sense because it is well adapted to late drilling, there is no reason to opt for spring wheat.”
Moreover, he adds, many growers forget how difficult spring cropping can sometimes be, as more is demanded from crops that at the same time can be less resilient to extreme weather events.
Nevertheless, variety choice is key to coaxing the best performance as later drilled wheat needs to have the vigour to get away despite the colder, wetter soils, and once spring arrives, to move quickly.
“Crispin makes a good choice as it can get going quickly, and the hard Group 4, Santiago is outstanding in the late slot in East Anglia,” says Mr Miles. “In addition, it gives a consistent specific weight of about 76kg/hl regardless of drilling date.
He also recommends growers consider sowing Siskin and Kerrin when drilling late because both show good speed of movement in the autumn and spring, with good grain quality and inherently high yield.
“Good seedbeds are a must and so is adjusting the seed rate to reflect both sowing date and seedbed conditions. Where crops get away perhaps too well, an early PGR will help support yields by evening the number of tillers.
“Beware of pushing drilling date too far however, as in poor conditions crops will struggle to develop a root system before winter.”
Late drilling top tips
- Seed rates should be adjusted upwards.
- Good seedbeds are a must: drill when the soil is in the best possible condition.
- Choose varieties with the best track record for performing at this time ie strong tillering; semi prostrate growth habit; faster plant development in the spring.
- The right winter wheat varieties can be drilled through to the end of January.
- Beware of pushing drilling date too far.