Tariff volatility in President Trump's second term has reintroduced significant uncertainty to the fertilizer market, leading U.S. farmers and agribusiness leaders to reconsider the country's reliance on global nutrient imports. In 2025 alone, three executive orders have directly addressed fertilizer supply chains, amplifying questions around input costs and the potential for expanded domestic production.

According to the USDA's Economic Research Service, fertilizer now accounts for between 33% and 44% of total corn production costs, making it one of the most critical and volatile expenses on the farm. The most commonly used fertilizers by volume are nitrogen, potash, and phosphates-and each presents a different sourcing profile with unique trade risks.

Potash remains the most import-reliant fertilizer in the U.S., with more than 95% of supply sourced internationally. Of that, roughly 87% comes from Canada, home to the world's largest producer, Nutrien, which exported over 14.4 million metric tons of potash in 2024. A smaller share, between 7% and 9%, originates from Russia, making it geopolitically vulnerable in today's shifting trade environment.

Though Canada remains a reliable supplier, the potential for tariff changes or logistical disruptions is prompting interest in reviving domestic potash mining. The U.S. has viable potash reserves in New Mexico, Utah, North Dakota, Arizona, and Michigan, but production remains limited due to high startup costs and long lead times.

Phosphate costs have also spiked, driven in part by China's recent halt of all phosphate exports-a drastic reversal from its position as the world's second-largest exporter before COVID-19. Previously supplying up to 8 million tons annually, China's exit from the global phosphate market has tightened supply and elevated prices, making phosphate the highest-cost fertilizer input relative to corn price, despite its lower application rates.

Globally, the top phosphate exporters are Morocco, China, Saudi Arabia, Russia, and the U.S. Meanwhile, potash exports are led by Canada, Russia, Belarus, Israel, and Germany-countries with varying degrees of trade stability and alignment with U.S. policies.

The question many in the ag sector are now asking is: Can the U.S. boost domestic fertilizer production to buffer against international shocks? While the U.S. produces a large share of its anhydrous ammonia domestically, the story is different for potash and phosphate-two inputs crucial for yield optimization and soil fertility in corn and soybean rotations.

The broader concern is not just about access but affordability. As fertilizer markets respond to geopolitical developments, environmental regulations, and logistical constraints, the possibility of continued price spikes in 2026 looms large. For many growers, especially those operating on thin margins, higher input costs could threaten acreage decisions and profitability in the next crop year.

Trade policy watchers also note that any future tariffs imposed on key exporters-Canada for potash or Morocco for phosphate-could further stress domestic markets unless new production capacity is developed. However, mining investments often require years of permitting and infrastructure buildup, making them a long-term-not immediate-solution.

For now, U.S. farmers are left to manage the risk. Vendor financing options, input co-op strategies, and long-term fertilizer contracts are among the tools being deployed to cushion against cost volatility.

As 2026 planting season approaches, the industry's eyes remain on Washington for further policy signals-and on global markets for signs of either stabilization or further disruption in the fertilizer supply chain.