6 steps to better spring barley yields

A wet autumn meant spring barley was a get-out-of-jail card for some growers last season. But many crops still delivered above average yields.

Their performance owes much to the age-old issue of tiller retention, says Limagrain arable technical manager Ron Granger.

Pictured below, Mr Granger outlines six ways to get the most from spring barley this coming season.

Depending on the locality and the opportunities for selling to different end users or export markets, the barley crop you grow and the agronomic inputs required will be determined by the sector you target.

End user requirements will influence many agronomic decisions, particularly nitrogen strategy. This makes it essential growers are clear about the quality criteria that must be met.

This is particularly true for those dependent on hitting a certain grain nitrogen percentage to achieve the contract premium, notably distilling, which requires 1.65% N or lower, brewing 1.65-1.85%, and grain distilling at 1.85%+. Grain nitrogen, generally, is not a concern for animal feed.

In many instances, variety choice is determined by the end user or contract chosen.

However, for those still to decide what to grow, consider one of the proven, dual use varieties, such as LG Diablo, which has good yield performance, with several end market opportunities.

Choosing a variety with greater tillering ability drives yield, and having more tillers helps crops compensate for tiller loss should stressful conditions arise.

Barley must go into a good seedbed with warming soils and temperatures to germinate and establish quickly, with continued plant growth, so patience is required to wait for the right window of opportunity.

Limagrain trials show earlier drilling in spring can improve yield potential, however, this is mainly only possible on lighter, more free-draining land, that will dry and warm quicker than a heavier soil type.

Early drilling will significantly increase disease risk, so consider more disease resistant varieties for this situation.

Weeds compromise crop establishment and tillering capacity, so drill into good conditions, and control early weed growth with effective chemistry sets that don’t knock early plant development.

For high yield potential, aim for a final tiller count of 775-800/m², and work back from this to calculate seed rate, varying according to soil type, drilling date, seedbed conditions, weather.

A survey of more than 100 growers by Limagrain in 2022 showed half (49%) of growers were typically sowing spring barley at 300-350 seeds/m² and most (76%) targeting a yield of 8t/ha.

Limagrain trials comparing variety seed rates over various seasons and regions suggest that with more vigorous, higher tillering varieties, such as LG Diablo, the optimum seed rate is 350 seeds/m² when drilling into ideal conditions around mid-March.

This should be adjusted up or down depending on the weather, seedbed quality, moisture availability, drilling date, and the grower’s own experience on each site.

A lower rate of 300-325 seeds/m² could suffice if drilling into an “onion bed” in March. But when forced to drill into April due to weather or agronomic reasons – such as black-grass control – pushing up rates to 400-450 seeds/m² may be more appropriate.

This will achieve the optimum final ear number and a competitive crop in a black-grass situation.

Once crops are established, the best way to achieve high spring barley yield potential is to ensure high final ear counts. The AHDB barley growth guide suggests final target ear population should be about 775 ears/m².

An 8-9t/ha crop needs around 800 ears/m², which equates to 350 seeds/m² to achieve 2.5-3 tillers per plant at harvest.

In some seasons, prolonged dry periods can cause crops to drop tillers and reduce yield potential. But last year, plentiful moisture availability throughout the growing season benefitted many spring crops, especially on lighter land. We cannot control the weather, but laying strong foundations at establishment will help crops produce and retain as many tillers as possible.

Balanced macro and micro nutrition improves rooting and canopy development, which benefits tiller survival. Apply most nutrition early, either to the seedbed or soon after drilling.

Spring barley has often been seen as a lower input crop, with growers reluctant to increase nitrogen application rates for fear of exceeding maltsters grain nitrogen limits. But don’t be afraid to push new, higher tillering varieties with more nitrogen.

Higher yielding varieties respond positively to higher nitrogen inputs, due to their increased yield potential and dilution of grain nitrogen content.

In our trials, an extra 30kg/ha of nitrogen applied in the second split generated 0.5-1t/ha extra yield in some varieties, with crops still achieving low grain nitrogen.

Alongside nitrogen, optimising other macronutrients – such as phosphate, potash, magnesium and sulphur – has benefited tiller retention and final yield.

Tissue analysis of the young growing crop can help identify any shortfalls in nutrition before visible symptoms appear and is a relatively inexpensive way of targeting a high yielding crop.

Additional micronutrients, such as manganese, zinc, copper, iron, and boron, applied at the stem extension phase into flowering, are also useful, ensuring a healthy crop and good ear fertility – while also helping to secure high grain numbers and maximum yield potential.

Also consider early growth regulator applications on crops to promote rooting and strong uniform tillering.

At least two fungicides are recommended to maintain tiller number and healthy plants, including the awns, for maximum grain development. Typically, the first application is at growth stage 25-31, with the second targeted at growth stages 39-55.

Spring barley can move through growth stages quickly, so close monitoring of the growing crop is essential for accurate application timings of product.