Planting decision
What survives my winter?
Enter a ZIP code. This reads your USDA hardiness zone and works through 74 perennial food plants — fruit trees, berries, perennial vegetables and herbs — telling you which live through an average winter where you are, which sit right on the edge, and which fail.
How this decides
Every perennial carries a hardiness rating — the coldest zone it comes through. The tool compares that against the USDA zone of your ZIP code. A full zone of headroom or more is a straightforward yes. Level with the rating, or half a zone above it, is the interesting answer: the rating describes an average winter, and half of winters are worse than average, so the plant survives most years and a hard one kills it. Those are worth planting with your eyes open, in the most sheltered spot you have.
Why some plants fail for being too warm
The answer people do not expect. Most temperate fruit needs a set number of hours below about 45 °F to break dormancy and set a crop, so an apple in zone 11 fails for want of winter rather than from it — and no amount of care substitutes. That is a different mechanism from the other warm-end failure, where it is summer heat and humidity that finish a plant off: currants and rhubarb cook, lavender rots at the crown. The tool separates the two, because the workaround is different. A low-chill cultivar fixes the first and nothing fixes the second.
Both of those upper limits are published as zone numbers, by convention, and that is the least precise thing on this page. A zone is a winter measurement being asked to stand in for a summer one, and it does that unevenly — a coastal zone 7 and an inland zone 7 are not the same summer at all. Treat a warm-end verdict as a flag to check your state extension service, not as a settled answer. The cold-end verdicts do not have this problem: there the rating and the zone are measuring the same thing.
What a hardiness zone actually measures
One thing only: the average annual extreme minimum temperature — how cold the coldest night of a normal year gets. That is all. It says nothing about summer heat, rainfall, humidity, soil or how long your winter lasts. Phoenix and coastal Oregon are both zone 9b and have almost nothing else in common.
So read a "reliably hardy" here as winter will not kill it, which is not the same as it will thrive. It is a floor test, and it is the single most useful floor test there is, but it is not a climate match.
The zone ranges for each plant are a judgement — conventional nursery and extension-service ratings — and they vary by cultivar, often by more than a full zone. Where a cultivar meaningfully changes the answer, the plant says so. They are not in the same tier as the zone itself, which is measured: the USDA 2023 Plant Hardiness Zone Map, built by PRISM at Oregon State from thirty years of station minima.
The other half of the year
This tool answers the winter question. For the summer one — how many growing days you have left and what still has time to mature — see what can I still plant?, which reads NOAA freeze normals from the weather station nearest you.