How We Research Product Claims
Our pages are source reviews, not hands-on product tests. Here is exactly how we collect, verify, and classify the evidence behind every claim.
We separate what a catalog or manufacturer says from independent agronomic context, and we preserve unknowns when an exact current label, cultivar identity, lot, or relevant trial receipt is unavailable. Nothing on a product page publishes without a claim class and a dated source it can be traced back to.
Our Research Process
Source Collection
We start with the product label, manufacturer specifications, and any published test data. For grass seeds, that means species composition, germination test results, weed seed content, and any coatings or treatments. For fertilizers, it means the NPK ratio, nutrient sources, and release profile. We also pull the current retailer or marketplace listing for the exact product we are covering.
Label & Data Verification
Every source gets checked against what it actually supports for the specific product and package we are describing — not the brand or product line in general. Where available, we cross-reference claims against NTEP (National Turfgrass Evaluation Program) trial data and university extension publications from programs like Penn State, Rutgers, and NC State, but only when the cultivar, trial location, and measured trait match the claim.
Claim Classification
Every claim we publish is tagged to an evidence class — see “What Our Classifications Mean” below — before it reaches a page. A claim that cannot be confirmed against a current label, lot, or dated source is flagged for manual review and does not get published as fact.
Dossier Review
An editor reviews the full source register and classification for a product before anything ships. We write original editorial notes grounded in that register — not rewritten marketing copy — and if the evidence has real gaps, we say so instead of filling them in.
Dated Re-Review
Dossiers get revisited when a claim goes stale, a source changes, or new information surfaces — not on a fixed calendar we promise in advance. Reviewing a public-safe subset of the evidence does not close a dossier out; unresolved claims stay flagged until they are actually resolved.
How We Weight Evidence
Not every source carries the same weight. We lean hardest on evidence tied to the exact product and package in front of us, and treat everything else as context:
Current package or seed tag
Primary weightCan support exact contents, test date, lot facts, and directions — but only for the specific package shown. A different size or lot may differ.
Manufacturer specifications
Supporting weightSupports attributed product positioning and specs. It reflects what the brand says about its own product, not independent verification.
NTEP & university extension data
Contextual weightProvides cultivar- or species-level context only when identity, trial, location, and measured trait match the specific claim. Never transferred to an unidentified blend or current retail lot.
Retailer & marketplace listings
Commerce-onlySupports commerce mapping — ASIN, buying path, listing status — only. Never treated as evidence for composition, agronomic fit, price stability, or performance.
What Our Classifications Mean
Every claim behind a product page is tagged with one of the classes below. A small number of claims fall into narrower edge classes — a seller-stated identity claim, or an inferred reading of an ambiguous source — and those get the same manual-review treatment as any other unresolved claim.
| Class | Meaning |
|---|---|
| repo-observed | A fact drawn directly from the current Premium Grass Seeds catalog — product identity, Amazon ASIN mapping, or how a listing is currently structured on this site. |
| manufacturer-stated | Sourced to the manufacturer's own materials — product description, formulation, or positioning. Reflects what the brand says, not independent verification. |
| research-backed | Sourced to NTEP trial data or university extension guidance, applied only when the cultivar, trial location, and measured trait line up with the specific claim. |
| marketplace-stated | Sourced to a retailer or Amazon listing — used for commerce mapping only, never as agronomic or performance evidence. |
| manual-review | Cannot yet be confirmed against a current label, lot, or dated source. Flagged rather than published as fact until a reviewer verifies it. |
What We Do Not Claim
- - We do not imply that we planted or field-tested a product without a cited test artifact.
- - We do not treat catalog scores, copied prices, or retailer stock text as current buyer truth.
- - We do not transfer cultivar trial results to an unidentified blend or current retail lot.
- - We do not call a dossier source-exhausted merely because a public-safe subset was reviewed.
How to Use a Product Page
Read the dated source note, follow its caveats, inspect the current package before use, and consult local extension guidance for site fit. If the evidence does not identify the exact product fact you need, treat it as unverified rather than filling the gap.
Browse research notesIndependence & Affiliate Disclosure
Premium Grass Seeds earns revenue through affiliate links. When you buy a product through our links, we may earn a small commission at no extra cost to you. This is how we fund our research and keep the site running.
Affiliate commissions never influence a claim's classification. Evidence is collected and classified using the process above before we ever look at affiliate rates. A commerce exit is a buying path, not proof of quality, performance, value, or fit.
We do not accept paid placements, sponsored reviews, or free products in exchange for coverage. See our full affiliate disclosure for details.
Questions About Our Process?
If you have questions about how we classified evidence for a specific product, or want to suggest a product for research, reach us at contact@premiumgrassseeds.com. You can also learn more about the team on our Editorial Team page.