MPS-ABC (plants and flowers)

MPS is the certification I look for first on potted plants. What I like about it is that it's built on measurement. It grades growers on what they actually use, which is exactly what sustainability should be: measuring and mitigating.

What it covers

MPS-ABC is an environmental certificate graded from A+ (best) to C. Growers record their use of crop protection products, energy, water, fertilizer and waste, and submit it to MPS every four weeks. Their use is compared with a standardized reference for their crop. After 13 months of reporting and an audit, the grower is certified and graded. MPS began with Dutch growers and is now run by a not-for-profit active in more than 50 countries, including North America.

Related certificates build on it: MPS-GAP covers good agricultural practice and requires MPS-ABC underneath, and MPS-SQ (Socially Qualified) covers health, safety and working conditions.

How it's verified

Independent audits and product sampling check the records growers submit.

What it doesn't mean

MPS-ABC on its own is environmental. For working conditions, look for MPS-SQ as well. And a C grade is a certification, but it's the lowest one, so ask for the grade, not just the logo.

What to ask

• What grade: A+, A, B or C?
• Do you also hold MPS-SQ?
• Can I see the current certificate and its validity dates?

Sources: MPS; Floristry Trade Club; Royal Green (MPS-ABC, GAP, SQ). Requirements change; check the certifier's current standard before relying on a detail.