Why buy certified seed potatoes?

Grigaitis Kęstutis
Aug 25
2 min read

In short: Certified seed potatoes guarantee varietal purity, lower risk of diseases, higher and more stable yields, and full traceability. In the European Union, seed potato trade is strictly regulated through official inspections and certification (European Commission – Council Directive 2002/56/EC).

Key benefits for farmers:

Higher and more reliable yields. According to FAO, using high-quality (certified) seed can increase yields by 30–50% compared to farm-saved seed.
Reduced risk of pests and diseases. Certification minimizes the spread of viruses (PVY, PVA), bacterial diseases (blackleg, ring rot), and potato cyst nematodes. The UNECE and FAO stress that seed quality is the foundation of pest and disease management.
Varietal identity and traceability. The OECD Seed Schemes ensure that certified lots carry an official label, proving the declared variety, category, and full lot history.
Compliance with EU law. The EU Directive 2002/56/EC states that seed potatoes can only be marketed if they are officially inspected and certified.

What does “certified” mean?

Field inspections and lab testing according to certification class (pre-basic, basic, certified).
Strict health standards – lots exceeding virus, pest, or disease thresholds cannot be certified.
Full traceability – official labels and documents with variety, class, lot number, crop year, certifying authority.
Harmonized trade rules – unified quality and labelling standards across the EU and OECD (UNECE Standard).

Myths vs facts

“Farm-saved seed is cheaper.”While it may seem cheaper at first, seed degeneration (virus, bacteria, nematodes) reduces yield and tuber quality every year. Research shows that seed quality is one of the main drivers of productivity (FAO report).
“Certification is just bureaucracy.”Certification is based on inspections, lab analysis, and strict international disease thresholds set by UNECE, OECD, and EU rules.

How to recognize certified seed potatoes

Official certification label with variety name, class (e.g. “Certified”, “Basic”), lot number, crop year, and certifying authority.
Supporting documents (certificate or plant passport) confirming compliance with EU Directive 2002/56/EC.

Benefits for your farm

Higher marketable yield – fewer rejected tubers.
Uniform quality – better size and shape consistency.
Lower costs and risks – fewer treatments for seed-borne issues and reduced chance of quarantine pests.

Choosing the right supplier

Buy from suppliers who provide transparent certification documents.
Select varieties that suit your soil, storage, and market needs.
Ask about the phytosanitary history (e.g. PCN status of fields). Guidance from AHDB and UNECE highlights the importance of PCN control in seed selection.