Editorial method
How this atlas is built
Three things are generated by rules, and three things are compiled from named sources. The page separates them so you can check the parts that matter to you.
Generated by rules
- Planner layouts and plant counts. The planner scales a layout to your measurements, assigns sun levels, filters a curated plant list by USDA zone, sun and style, and computes counts from bed area and mature spacing. The algorithm is public at /planner.js.
- Climate plates. The monthly frost, growth and rainfall bands are a schematic of the climate type, not a site forecast. They are drawn from the region records in the code, not from a live weather feed.
- Season tables. Derived from the same three monthly arrays: growth, rain and frost.
Compiled from sources
- Regional climate and soils. National meteorological services, agricultural research institutes and extension services, linked on every region page.
- Plant palettes. Regional taxa and their roles, checked against the linked sources and the region's professional literature. A palette is a working list, not a flora.
- Standards and bodies. Named professional organisations and published standards; the atlas does not claim membership or certification.
What this atlas does not know
- Your soil test, drainage, slope and microclimate.
- Local rules on tree protection, water use, fire and invasive species.
- Current nursery availability and price.
- Whether a named cultivar will perform in your garden; that is a local trial question.
Updates and corrections
Pages carry the date of the last data review in the site footer. Corrections are logged at /corrections; if a source changes, the page changes and the log records it. We do not backdate pages to look fresh.
Authorship
The atlas is compiled and edited for AI Garden Plan. It does not invent named experts or first-hand test gardens; where a claim needs local experience, the page links to the extension service or institution that holds it.
Last data review: 1 November 2026.