Free keyless JSON API: 2023 USDA plant hardiness zone (and 2012 zone) for any U.S. ZIP code, from the PRISM Group / Oregon State University ZIP listings. Open CORS, HTTPS, no key. Docs: https://usgrowzones.com/developers/?utm_source=reqistry&utm_medium=directory&utm_campaign=backlinks
Limited evidence: 50% of weighted signals verified. Treat this score as provisional.
50% of weighted signals verified · unverified: documentation quality, auth clarity, CORS, pricing clarity, OpenAPI availability
Not enough verified evidence for a production recommendation.
| Authentication | NONE |
|---|---|
| Pricing | FREE |
| Rate limit | not yet verified |
| Credit card required | not yet verified |
| Commercial use allowed | not yet verified |
| Health status | DEGRADED |
|---|---|
| Uptime 24h | 100% |
| Uptime 7d | 100% |
| Uptime 30d | 100% |
| Response time | 135 ms |
| Trust score | 75 (grade B) |
| Evidence confidence | 50% |
| Unverified signals | documentation quality, auth clarity, CORS, pricing clarity, OpenAPI availability |
| Last checked | 2026-11-05T02:45:15.472Z |
| Field | Source | Verified at |
|---|---|---|
| pricing | not yet verified | not yet verified |
| authentication | not yet verified | not yet verified |
| documentation | not yet verified | not yet verified |
| cors | not yet verified | not yet verified |
Data updated 2026-11-05T02:45:15.472Z
Free · API Key auth
Free · API Key auth
Unknown · Unknown auth
Freemium · Unknown auth
Free · Unknown auth