Grimes, IA 50111 Frost Dates
Grimes, IA: when does the frost end?
Typically, the last spring freeze lands around 04/19, roughly 234 days out. Fall's first freeze usually shows up around 10/18, roughly 179 days after the last spring frost.
Grimes sits in USDA Zone 5b (-15 to -10°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
With roughly 7 weeks until Grimes's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
04/19 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/05 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/03 and only about 1 year in 10 sees frost after that.
Grimes against the rest of the dataset
At roughly 179 frost-free days, Grimes places 25,213 of 40,283 ZIP codes in this dataset. Within IA, it ranks 99 of 1,042.
Learn more
Before leaning on 50111's figures: local microclimates explains what one yard in Grimes can differ from the 50111 normal, while zone vs. frost date explains why Zone 5b and Grimes's frost date answer different questions.