Video: Fertiliser spreading strategies for winter hybrid barley
Despite the challenges of a difficult drilling period, the area of winter hybrid barley sown increased in autumn 2017.
This is as a result of consistent and reliable performance – both on farms and in Department of Agriculture trials.
Newer hybrid barley varieties – such as Quadra, Bazooka and Belfry – offer a significant yield advantage over conventional barley varieties and are equal to or better on grain quality, agronomy and straw characteristics.
In terms of total inputs, hybrid barley can generally be treated as a conventional two or six-row winter barley variety and it is an easy crop to grow.
Due to its vigorous growth habit, hybrid barley begins its spring growth early and needs to be managed by growth stage; not by traditional calendar timings.
In order to maximise yields and profits with hybrid barley, growers should follow four simple agronomy steps.
As spring kicks off and growers consider their fertiliser programmes, there are some key factors to review before the first fertiliser application.
Tim O’Donovan, technical director of Seedtech, recently spoke to Teagasc fertiliser expert Dr. Richie Hackett about the upcoming fertiliser spreading season and the approach farmers should take.
Dr. Hackett first outlined the importance of completing and analysing soil test results in order to work out potassium (K) and phosphorus (P) inputs.
How much P and K for a 10t/ha crop of hybrid barley
The higher yield potential of hybrid barley means that growers need to replace nutrients removed in grain (mainly P) and straw (mainly K). The absence of regular and accurate soil tests means that growers could be spreading fertiliser incorrectly and limiting the crop’s yield potential.
Potassium plays an important part of straw strength and is akin to steel bars in a concrete wall. Ideally, the P and K should be applied in the first application or split between the first and second applications.
Where soil fertility is low, lime is vital to releasing nutrients held in the soil and making best use of applied nutrients. Organic manures need to be accounted for if used.
Adding to this, Dr. Hackett said: “The other thing to do is to look at your historical yields, so that you can work out your fertiliser nitrogen (N) allowance.”
If the crop is after beans or other breaks, there will be residual nitrogen that the vigorous roots of hybrid barley can mop up and convert into yield; saving the grower money.
When deciding how much nitrogen to put on the crop, he added: “A grower will need two pieces of information – the N index, which is based on the previous crop in the field, and the historic yields in the last three years (this is also a Nitrates Directive requirement).”
How much N to apply to a crop of hybrid barley
As there was a wide range of drilling dates last autumn, courtesy of hurricane Ophelia, there will be a wide range in crop development stages this spring; even between neighbouring fields.
Many trials conducted by Dr. Hackett into winter barley and fertiliser strategies conclude that the first split of N should be applied before the crop finishes tillering or at growth stage 23-25 (when the plant has three-to-five tillers). This is where assessing the crop is critical.
On this subject, he said: “The next step is to assess the crop, including: plant count; tiller counts; and growth stage.
“Typically, growth stage 23, 24 or 25 is the right time for hybrid barley’s first split of fertiliser. Farmers should take care not to count the main stem when tiller counting to establish the crop’s growth stage.”
When to apply fertiliser splits to hybrid barley
O’Donovan concluded that in order to get the most out of your investment in fertiliser and produce more grain and profit with hybrid barley, barley growers should:
- Access previous cropping history;
- Complete a soil test and implement a P and K strategy appropriately;
- Access crop growth stage.
By following these simple steps, growers can be safe in the knowledge that they have applied their fertiliser based on proven Irish science and made adjustments based on the crop of hybrid barley they are growing.