Hamburg, IA 51640 Frost Dates
When can you plant in Hamburg, IA?
Around 04/19 is the usual last spring frost, about 234 days away. The first fall frost typically arrives around 10/19, about 182 frost-free days later.
The USDA Plant Hardiness Zone Map puts Hamburg in Zone 5b (-15 to -10°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
About 7 weeks of growing season left in Hamburg before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Hamburg's last frost
04/19 is the middle of 30 years of NOAA records, not a promise. Plant by 04/05 and you're betting against frost in roughly 9 years out of 10. 05/02 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Hamburg compares
At roughly 182 frost-free days, Hamburg places 24,241 of 40,283 ZIP codes in this dataset. Within IA, it ranks 82 of 1,042.
Learn more
local microclimates covers what one yard in Hamburg can differ from the 51640 normal. zone vs. frost date covers why Zone 5b and Hamburg's frost date answer different questions.