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LCF Australia

Crop guide

Barley nutrition

Nutrient needs, growth stages, common deficiencies and why nutrients go missing in Australian feed and malting barley.

Nutrient needs

Barley responds to nitrogen much like wheat, but malting barley has to land inside a grain-protein window to make grade. Too little nitrogen costs yield. Too much, or nitrogen applied too late, can push protein above the malting range and increase lodging.

Phosphorus at sowing supports early root growth and tillering. Sulphur, potassium, zinc and manganese can all limit barley on the soils where they are commonly short. Barley is also sensitive to acidic soils, so soil pH and liming are part of the nutrition picture.

The target market changes how much nitrogen suits the crop. A feed crop can carry more nitrogen than a crop aimed at malting.

Ground-level view across a dense green barley crop stretching to a flat horizon under a blue sky with white clouds
Barley grown with Urea Plus near Horsham, Victoria, 2026, seen from ground level. Results will be published after harvest 2026. Photo: LCF Australia. This is a general crop photo, not a deficiency photo.

Key nutrients

Growth stages and when nutrients matter

  1. Stage 1

    Sowing and establishment

    Phosphorus and any starter nitrogen go in at sowing. Zinc is often included with the seeding fertiliser where soils are prone to deficiency.

  2. Stage 2

    Tillering

    Adequate nitrogen supports tiller numbers, which set the potential head count.

  3. Stage 3

    Stem elongation

    Nitrogen taken up now mainly supports yield. In malting barley, extra nitrogen also raises the chance of grain protein above the malting range.

  4. Stage 4

    Late season

    Late nitrogen tends to raise grain protein more than yield. That can help a feed crop but push a malting crop out of specification.

Common deficiencies and signs

Symptoms of different problems can look alike. Disease, herbicide damage, waterlogging and frost can all produce signs similar to a deficiency.

Nutrient What to look for Where it is more likely
Nitrogen Pale older leaves and thin stands with few tillers. Most soils, especially after cereals or in wet seasons.
Phosphorus Stunted, slow plants with dark or purplish older leaves. Low-phosphorus soils and soils that tie up phosphorus.
Manganese Interveinal yellowing and brown spots, often in patches. Calcareous and alkaline sands and loose seedbeds.
Zinc Pale blotches and stripes on leaves and poor early growth. Alkaline and calcareous soils and some sands.
Sulphur General yellowing that shows first on younger leaves. Sandy, low organic-matter soils and after heavy rain.

What deficiencies look like in barley

Photos of deficiency symptoms. Where we do not yet have a suitable photo, we will add our own trial photo. Symptoms vary with crop, variety, soil and season.

  • Manganese deficiency in barley. We will add our own trial photo here.
  • Nitrogen deficiency in barley. We will add our own trial photo here.

Photos may show other crops with the same symptom. Full credits: Image credits.

Why nutrients go missing

Not everything applied to a barley crop ends up in it. These are the main ways nutrients are lost or become unavailable.

Volatilisation
Urea left on the soil surface is converted to ammonium and then to ammonia gas, which can escape to the air. The loss is greater on warm, moist soils with no follow-up rain, on alkaline soils and under heavy surface stubble.
Leaching
Nitrate and sulphate dissolve in soil water and move down with it. On sandy soils, heavy rain can carry them below the root zone.
Denitrification
When soil is waterlogged, oxygen runs short and soil bacteria convert nitrate into nitrous oxide and nitrogen gas, which are lost to the air.
Immobilisation
Microbes breaking down cereal stubble take up soil nitrogen for their own growth, holding it out of the crop’s reach until they die and release it.
Phosphorus fixation (lock-up)
Phosphorus reacts with calcium in alkaline soils, and with iron and aluminium in acidic soils, forming compounds plants cannot easily use. It also moves very little in soil. Calcareous soils and soils with a high phosphorus buffering index (PBI) bind more of it.
Trace element lock-up
At high soil pH, zinc and manganese form compounds of low solubility, so calcareous and alkaline soils can hold these elements yet supply little to the crop. Cold, wet soils slow root activity and uptake further.
Late nitrogen and protein
Nitrogen taken up late in the season goes mostly into grain protein rather than yield. In malting barley, that can push grain outside the malting specification.
Seed-row effects
As urea dissolves next to the seed it releases ammonia, which can damage germinating seed. The effect is stronger with wider rows, narrower openers, sandy soils and dry seedbeds. Cereals are less sensitive than canola and pulses, but still affected at higher rates.

LCF offers fertiliser technology matched to your use case, whether that is drilled urea or top dressing before or after planting. Advanced inhibitor technology is added in the compounding process at our manufacturing partner Lardmee (LDM).

How we match technology to your use case

How LCF products fit

LCF Australia supplies compound fertilisers made by our manufacturing partner Lardmee (LDM), including Urea Plus and zinc and manganese sulphates, on enquiry. We also supply the Field Spears soil testing kit, which reads soil N, P, K and pH in the paddock. Which product suits, how much and when depends on the soil, the crop, the season and how you apply it.