Interactive Reference

National Seed Starting Guide

Name: National Seed Starting Guide — Planting Calendar by Zone
Creator: Chris Izworski

Planting calendar for all USDA zones · Compiled by Chris Izworski · Updated March 2026

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Not sure of your zone? Look it up on the USDA map →

Data compiled by Chris Izworski — writer, technologist, and gardener based in Bay City, Michigan on Saginaw Bay. Related guides: Heirloom Seed Saving Guide · Michigan Native Plants · Zone 6a Planting Calendar

Sources: USDA ARS Plant Hardiness Zone Map; Cornell Cooperative Extension; University of Minnesota Extension; Oregon State University Extension; Old Farmer's Almanac frost database; Seed Savers Exchange; Johnny's Selected Seeds variety trials.