Watertown, WI 53098 Frost Dates
When can you plant in Watertown, WI?
The last spring frost here typically falls around 04/28, about 243 days from today. The first fall frost typically arrives around 10/12, about 167 frost-free days later.
The USDA Plant Hardiness Zone Map puts Watertown in Zone 5a (-20 to -15°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 Watertown 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
04/28 is the middle of 30 years of NOAA records, not a promise. Plant by 04/14 and you're betting against frost in roughly 9 years out of 10. 05/13 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Watertown compares
About 167 days separate Watertown's last and first frost, putting it 29,885 of 40,283 ZIP codes nationally. Within WI, it ranks 151 of 860.
Learn more
local microclimates covers what one yard in Watertown can differ from the 53098 normal. zone vs. frost date covers why Zone 5a and Watertown's frost date answer different questions.