Home / USDA zones / USDA to ANBG
USDA hardiness zone is used in United States; Australian (ANBG) zone is used in Australia. Both are anchored to temperature, so they can be lined up — but they divide the scale differently, and one band in one system often spans two in the other. Treat the table below as the nearest equivalent, not a precise translation.
They are not the same kind of claim. Plant tolerates down to this zone. Plant tolerates down to this zone. That difference matters more than the numbers: reading one as though it were the other is the single most common way a plant ends up bought for the wrong garden.
USDA to ANBG conversion table
| USDA | Temperature range | ANBG equivalent | What it means |
|---|---|---|---|
| Zone 1 | down to −45.6 °C | no direct equivalent | Sub-arctic — winter lows below −45 °C |
| Zone 2 | −45.6 °C to −40 °C | no direct equivalent | Severe continental cold |
| Zone 3 | −40 °C to −34.4 °C | no direct equivalent | Very cold winters |
| Zone 4 | −34.4 °C to −28.9 °C | no direct equivalent | Cold winters, short growing season |
| Zone 5 | −28.9 °C to −23.3 °C | no direct equivalent | Cold continental winters |
| Zone 6 | −23.3 °C to −17.8 °C | no direct equivalent | Moderately cold winters |
| Zone 7 | −17.8 °C to −12.2 °C | Zone 1 | Mild cold winters |
| Zone 8 | −12.2 °C to −6.7 °C | Zone 1, Zone 2 | Mild winters with light freezes |
| Zone 9 | −6.7 °C to −1.1 °C | Zone 2, Zone 3 | Light frost only |
| Zone 10 | −1.1 °C to 4.4 °C | Zone 3, Zone 4 | Near frost-free |
| Zone 11 | 4.4 °C to 10 °C | Zone 4, Zone 5 | Frost-free, warm winters |
| Zone 12 | 10 °C to 15.6 °C | Zone 6, Zone 7 | Tropical |
| Zone 13 | 15.6 °C and warmer | Zone 7 | Hot tropical |
Why the conversion is approximate
A plant rated USDA zone X survives in zone X and warmer. Your zone number should be at or above the plant's rating to grow it outdoors.
Australian National Botanic Gardens zones run from 1 (cold mountain) up to 7 (hot tropical). The system only covers down to about −15 °C — colder climates fall outside it.
Because the two systems were built for different places and different questions, a converted number tells you roughly where a plant sits on the cold scale — not whether it will thrive. Summer heat, humidity, rainfall pattern and the length of your growing season all matter, and none of them appears in either rating.
Check a rating against your own conditions
Converting the number is only half the job. Cross-check a rating against your own climate, or find your zones in all four systems by answering a short set of questions about where you garden.
See also the full band tables for USDA hardiness zone and Australian (ANBG) zone.