Urea prices hit $850 per metric ton in April after Strait of Hormuz closure cut one-third of seaborne fertilizer trade

The Iran conflict shut the Strait of Hormuz, blocking 31% of seaborne fertilizer tonnage and idling 31 Middle East ammonia plants. Domestic US nitrogen output covered most demand, yet Persian Gulf imports still transmitted the price shock. Urea futures rose from $470 to $850 per metric ton between January and April before partial recovery. World Bank trade-flow data and CoBank supply audits show 20 additional Russian ammonia units offline since 2022, compounding the 2026 shortfall. Pivot Bio and Switch Bioworks microbial products avoided natural-gas inputs and held flat pricing, yet they represent under 1% of applied nitrogen. Emissions accounting places conventional ammonia synthesis at 2% of global CO2-equivalent output. Long-term contracts now embed three-year price locks at microbial suppliers while conventional forecasts from CoBank project sustained elevation above $600 per ton through 2028. Farmers facing diesel and fertilizer correlation face margin compression that transmits directly to retail food indices. Operational substitution requires verified field-trial nitrogen replacement rates above 60% before scale alters global trade exposure.