New EU Rules on Nitrogen Use in Potato Farming: What's Changing for Farmers

2026 has brought several significant changes to nitrogen use in agriculture – both from the European Union and at national level. For potato growers, for whom nitrogen is one of the most yield-critical inputs, it's worth knowing exactly what has changed and which deadlines are already in effect.

A new EU Nitrates Directive amendment: RENURE fertilizers

In March 2026, European Commission Directive (EU) 2026/288 entered into force, amending Council Directive 91/676/EEC (the Nitrates Directive) regarding the use of certain fertilizing materials derived from livestock manure. The directive introduces an exemption for so-called RENURE fertilizers (REcovered Nitrogen from manURE) – mineral nitrogen fertilizers produced through a specific technological process from manure.

For fertilizers to qualify as RENURE, each batch must maintain consistent quality: the ratio of mineral nitrogen to total nitrogen must be at least 90%, or the ratio of organic carbon to total nitrogen must not exceed 3. Strict heavy metal limits in dry matter are also set: copper (Cu) at 300 mg/kg and zinc (Zn) at 800 mg/kg. National legislation implementing this directive, including in Lithuania, must take effect by March 2, 2028.

Current nitrogen, phosphorus and potassium limits in Lithuania

When fertilizing with organic fertilizers (manure and slurry), the total amount of nitrogen (N) applied to soil per calendar year may not exceed 210 kg/ha, phosphorus (P2O5) 90 kg/ha, and potassium (K2O) 240 kg/ha. Farms with a fertilization plan based on soil test results no older than 3 years may apply higher amounts: nitrogen up to 250 kg/ha, phosphorus up to 150 kg/ha, potassium up to 300 kg/ha. These are the maximum limits set by law – exceeding them is considered a violation.

Mandatory electronic logs for all farmers

Since January 1, 2026, all users of plant protection products and fertilizers in Lithuania must keep electronic logs of Plant Protection Product (PPP) and Fertilizing Product (FP) use. Previously, this obligation only applied to farms of 150 ha or more (from April). It now extends to all farms regardless of size. A fine of €750 applies for failing to keep the log or for exceeding fertilizer limits.

Fertilizer prices: the CBAM effect

Since 2026, the EU's Carbon Border Adjustment Mechanism (CBAM) also applies to imported fertilizers. It's estimated that for every tonne of nitrogen fertilizer, whose production emits 2–3 tonnes of CO2, an additional €120–180 will need to be paid. Fertilizer prices are forecast to rise 5–15% in 2026, depending on the production method. European farmers' organizations COPA and COGECA have already called for delaying CBAM's application to fertilizers, arguing the price rise could seriously harm the agricultural sector.

What this means for potato growers

Potatoes are one of the most nitrogen-sensitive crops – based on neighboring Germany's model, depending on planned yield, the upper nitrogen limit for potatoes can reach around 180 kg/ha. For potato growers, the priorities now are: updating soil tests in time (so higher limits with a fertilization plan remain valid), setting up electronic log-keeping from the start of the season, and evaluating whether RENURE fertilizers, once available on the Lithuanian market, could become a cost-effective alternative to increasingly expensive imported nitrogen fertilizers.