Recent developments in genetics mean many of the highest yielding and best performing wheat varieties can now be safely grown into December and beyond.
Growers who get their variety choice right can reap significant benefits from later drilling, says John Miles of plant breeders KWS UK. The key is to recognise the differences in environmental conditions late-drilled wheat faces, he adds.
“Later drilled wheat crops can deliver high yields while offering better blackgrass control options and being cleaner with lower growing costs than their September-sown counterparts,” says Mr Miles.
“In reasonable conditions, 10t/ha plus crops are on the cards for most late-drilled wheats but variety choice is key. Sow a variety not suited to this slot and you could easily suffer 20-30% yield loss.”
While earlier drilled wheats benefit from warmer days and a longer growing season, later drilled wheat faces more compromised conditions including colder air and soil temperatures – and often wetter soils with less mineralisation.
“Depending on how soils are worked, seedbed conditions or soil to seed contact could also be affected,” says Mr Miles. Direct drilling and use of cover crops can allow soils to be in better condition later in the season, he adds.
Specific varietal traits can go a long way to mitigating these disadvantages. Growers should look for an aggressive plant type with a lot of get up and go to help smooth out the compromises and variability that result from later drilling.
“High autumn vigour and speed of movement in the spring to extend the grain-fill period are critical as are supercharged tillering potential, strong root development and the ability to tiller strongly at lower temperatures.”
With Recommended List trials now being drilled mid-October, the varieties growers are looking at on the list are typically very different from those from ten years ago when trials were drilled in September, explains Mr Miles.
“Generally, you can have confidence in the varieties available in terms of their recommended drilling but if you want to be really sure or are in a marginal area, then look for the proven performance of varieties identified in the late-sown RL.”
Ideal choices until the end of November would be the KWS varieties Lili, Kinetic, Jackal, Zyatt, Barrel and Bassett, whilst Kerrin, Extase, Siskin, Crispin and the new Cranium continue to deliver strong performances drilled up to the end of December.
Some varieties, such as KWS Firefly continued to deliver peak performance right through to the end of February. But Mr Miles says it is not a good idea to simply use up some mainstream seed in the late-drilled slot.
“The yield difference between a variety on the late-drilled RL and one that is not could easily be 2-3t/ha – with much of that down to tillering
capability. Thin crops stay thin as it’s hard to grow additional tillers – you can drop tillers but you can’t really add any.”
Although last year’s sowing conditions were challenging, growers should take heart from the resilience of the best varieties. You only have to think about last year to get an idea how strong the genetic material we now have is, says Mr Miles.
“Those lucky enough to get wheat in the ground last autumn were still pushing out 7-8t/ha, despite two months less growing time and horrific seasonal conditions ranging from plants being waterlogged to six weeks of drought and extremely hot spring temperatures.
“But if you want to get the most out of your late-drilled wheats this year, variety choice is critical and you then need to make sure you look after them in terms of things like early N to get them tillering early and then able to keep them later.
“If you do choose carefully, you’ll get the yield plus your crops are likely to be cleaner in terms of lower disease pressure, so they can actually be cheaper to look after because you are putting them in a lower risk slot.”