Bulbing onions that must be matched to local day length.
Choose the region that actually covers your garden. These source references are not a nationwide planting calendar.
2–4 weeks before the spring frost reference
The source anchor is the average last spring frost. Use this as an approximate regional starting point.
A NOAA station’s median 32°F freeze date is a different measure. Substituting it is an application calculation, not a published local calendar.
Use the Central North Carolina calendar, with its separate establishment methods. This is not a calendar for every part of North Carolina.
Use the Florida calendar for your specific subregion. Planting months are not interchangeable across the state.
The source uses an older family classification, so its family label may differ from the one shown here.
Outside these regions? Use your local Extension planting guidance. A nearby weather station describes climate; it does not establish whether or when to plant this crop.
These ranges start at different stages. Keep the method, region, and crop type attached to every number.
Count from planting bulbs or cloves. A seed-based range is a different starting point.
Count from seed sown directly in the garden.
Maturity references vary with cultivar, harvest size, weather, and establishment method. Keep your seed packet or transplant label alongside the regional calendar.
Published germination minimum · Colorado
A source germination minimum, not an optimum or a transplant threshold; do not treat the number as a guarantee.
Read soil-temperature sourceSelected source facts reviewed . This is our review date, not the sources’ publication date.
How we use the data