When a package says "compostable," the label is only half the story. What matters is where it composts. A "home compostable" product breaks down in a backyard pile at ambient temperatures, within a season or so. An "industrially compostable" product — the category most compostable packaging belongs to — requires sustained high heat, moisture, and microbial activity found only in a commercial composting facility.
That distinction decides whether a bag actually biodegrades. A certified industrial-compostable film tossed in a backyard bin will sit there largely intact for months; the same film sent to a commercial composter disintegrates within the certified 90-day window. PLA is a textbook case: it needs temperatures around 58°C that a home pile rarely reaches, which is why credible PLA products carry ASTM D6400, EN 13432, or GB/T 19277 marks — all standards for industrial composting.
Three practical takeaways. First, a landfill is not composting: buried under trash with no oxygen, compostable plastics barely degrade at all. Second, keep compostable plastics out of the recycling stream — PLA looks like PET but contaminates PET bales. Third, read the certification, not just the claim: the standard tells you which facility the product was designed for.
Greenstar's bag lines are certified to ASTM D6400, EN 13432, and GB/T 19277 for industrial composting — a promise that only holds if the bag reaches the right end of life.
Disclaimer: Product descriptions, specifications, and certification references in this article are provided for general information. Compostability claims (including ASTM D6400, EN 13432, and GB/T 19277) refer to industrial composting conditions; commercial composting facilities may not be available in all communities. Certifications apply only to the specific products listed in the relevant certificates. For current certification documentation, contact Greenstar@greenstarmaterial.com.