USDA HARDINESS ZONES

the 13 zones by average annual extreme minimum — each range in °F and °C, with the a and b half-zones

Built as a memo rather than a table: the thing worth hanging it up for reads across the room, with the full reference in smaller type below it.

Three sizes in one archive — from a sheet on the fridge to a poster on the wall.

Formats: A4 · A3 · A2
What you get: Print-ready PDFs, one per size, with every letterform converted to outlines — nothing to install, nothing to shift.
Subject: science · reference · everyone · study

Zone boundaries are the USDA definition: average annual extreme minimum temperature in 10 °F bands, with 5 °F half-zones a and b. The current map is the 2023 edition built on PRISM 1991–2020 data. Look up your own zone by address at planthardiness.ars.usda.gov. Celsius is computed as (F−32)·5/9 and rounded to one decimal. Checked 2026-08-13.

THE MAP MOVES, BECAUSE IT IS CLIMATE, NOT GEOGRAPHY

A zone is not a property of a place; it is a sliding thirty-year window of measurements. When the USDA recomputed the map in 2023 from the 1991–2020 record, replacing the 2012 edition, about half of the country shifted to the next warmer half zone — not because anything moved, but because the winters themselves did.

Where the shift happened it amounted to 0–5 °F. That is why a zone is looked up on the current map rather than remembered from childhood: the number at the same address may have changed.

On the sheet

Zone boundaries are the USDA definition: average annual extreme minimum temperature in 10 °F bands, with 5 °F half-zones a and b. The current map is the 2023 edition built on PRISM 1991–2020 data. Look up your own zone by address at planthardiness.ars.usda.gov. Celsius is computed as (F−32)·5/9 and rounded to one decimal. Checked 2026-08-13.
Colour carries meaning, but meaning never rests on colour alone — the sheet reads in black and white.
Nothing about how it was made: the sheet carries only what the reader needs.

Printing

Three sizes in the archive: A4 — 210×297 mm, A3 — 297×420 mm, A2 — 420×594 mm.
All text is converted to outlines. No fonts to install, and nothing shifts on another machine.
White background and sparing fills — it prints on a home printer without draining the cartridge.
Margins of at least 10 mm: a home printer cannot print to the edge.
No stroke thinner than 0.3 mm, so nothing disappears in print.

Why the numbers can be trusted. Every countable number here is computed from data rather than typed in, and the sheet must pass 9 independent checks before it is allowed to build — how many items there are, the order they come in, and the claim in the highlighted box itself. If one fails, there is no file.

USDA HARDINESS ZONES

THE MAP MOVES, BECAUSE IT IS CLIMATE, NOT GEOGRAPHY

On the sheet

Printing

More like this

THE BEAUFORT SCALE

THE EIGHT BLOOD TYPES

RED CABBAGE pH INDICATOR

THE TEN CLOUD GENERA