New London, IA 52660 Frost Dates
When can you plant in New London, IA?
Around 04/30 is the usual last spring frost, about 245 days away. The first fall frost typically arrives around 10/10, about 163 frost-free days later.
The USDA Plant Hardiness Zone Map puts New London 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 6 weeks of growing season left in New London before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
04/30 is the middle of 30 years of NOAA records, not a promise. Plant by 04/13 and you're betting against frost in roughly 9 years out of 10. 05/14 is the safer bet, historically only a 1-in-10 chance of frost that late.
How New London compares
New London's growing season runs about 163 days, ranking 31,410 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 664 of 1,042.
Learn more
local microclimates covers what one yard in New London can differ from the 52660 normal. zone vs. frost date covers why Zone 5b and New London's frost date answer different questions.