About GrowByCity
GrowByCity provides free planting calendars powered by climate data from NOAA, FAO, and Open-Meteo. Our mission is to help gardeners around the world know exactly when to plant, based on real climate data rather than guesswork.
How It Works
We combine local frost dates, USDA hardiness zones, average temperatures, and rainfall data to calculate optimal planting windows for each crop in each city. Our algorithms consider minimum and maximum temperature tolerances, frost sensitivity, and growing season length to provide personalized recommendations.
Who Built This
GrowByCity was created by the GrowByCity team, a team of gardening enthusiasts and data engineers. After finding that most planting calendars only cover US ZIP codes, we built GrowByCity to provide climate-driven planting recommendations for cities around the world — from Tokyo to Toronto.
Our Data Sources
- NOAA (National Oceanic and Atmospheric Administration) — Historical climate and frost date data
- FAO (Food and Agriculture Organization of the UN) — Agricultural growing requirements and crop data
- Open-Meteo — Climate API providing temperature, precipitation, and weather pattern data
- USDA Plant Hardiness Zone Map — Zone classifications based on average annual minimum temperatures
How We Ensure Accuracy
Planting windows are calculated algorithmically from verified climate data — not guesswork. We combine frost dates, temperature ranges, and hardiness zones with each plant's specific growing requirements. Our data is refreshed with the latest climate records, and every city page shows the source data used. If a planting date seems off for your area, please let us know so we can investigate.
Disclaimer
GrowByCity provides general planting guidance based on climate data. Actual conditions may vary from year to year. Microclimates, soil conditions, elevation, and other local factors can affect growing success. Always consider your specific garden conditions when making planting decisions.
Last updated: March 2026