Nitrogen Fertilization for Barley: Optimal N Rates and Timing
Barley is cultivated on over 1.5 million hectares in Germany as both winter and spring varieties. Whether grown for malting, brewing, or feed, the nitrogen rate matters both for yield and for grain quality. Barley has a distinctly lower nitrogen requirement than wheat, and excess N is more damaging here than in most other cereals.
Nitrogen Demand and Yield Response
Germany's average barley yield is around 6.3 t/ha (Destatis 2022). The nitrogen response curve, supported by Stram & Macholdt (2021), shows a strong yield increase in the first 60 kg N/ha range, with rapidly declining returns beyond 120 kg N/ha. Regional advisory tables for Germany commonly cite around 120 kg N/ha for winter feed barley at reference yield — but note that official DBE Bedarfswerte are state- and crop-classification-specific, distinguishing at minimum winter vs. spring barley and feed vs. malting barley. The figures in this article are agronomic guidance; always verify with the applicable current state DBE table for legal nutrient planning. Adjustment factors of ±10 kg N per ±10 dt/ha deviation are typical in advisory practice.
Malting vs Feed Barley
This distinction is commercially critical. Malting barley requires grain protein below 11.5%. Excess late nitrogen raises protein above this threshold and disqualifies the crop from premium malt contracts. For malting varieties, a reduced second split or a single early application is often preferable. Feed barley has no such constraint and can be managed at the upper end of the economic optimum range.
Application Timing
Winter barley typically follows a two-split approach:
- First application (BBCH 25–30): 50–70 kg N/ha for tillering and early stem elongation
- Second application (BBCH 32–39): 40–55 kg N/ha for stem elongation — reduce for malting varieties
Spring barley generally receives a single application at sowing or shortly after emergence (60–100 kg N/ha). Splitting spring barley rarely produces a significant economic benefit under typical German conditions (KTBL 2018).
Economic Optimum
The profit-maximising rate shifts with the grain-to-fertilizer price ratio. At €20/dt barley and €1.20/kg N, the economic optimum is typically 15–25 kg below the agronomic yield maximum. This gap widens as fertilizer prices increase. See how prices drive the N optimum.
Nmin and Adjustments
Always subtract the Nmin value (0–60 cm) from the planned application. After a legume previous crop, apply a 20–40 kg N/ha credit. High winter rainfall can both raise Nmin through mineralization and lower it through leaching — measure rather than estimate. For more, see Using the Nmin Value Correctly.
Conclusion
Barley rewards a targeted, split approach that prioritises early N for yield and limits late N for quality. Getting prices and Nmin into the calculation consistently outperforms fixed-rate recommendations.
Calculate your barley N rate with current prices: Open the NRate Calculator