Frost Dates for Oshkosh, WI

In Oshkosh, WI, the average last spring frost is around Apr 24 and the average first fall frost around Oct 20, for a growing season of about 178 days. For frost-tender plants, wait until May 8, when the chance of frost drops to 10%.

Average last frostApr 2450% chance of frost after this date
Safe to plantMay 8only a 10% chance of frost after
Average first frostOct 2050% chance of frost before this date
Growing season178 daysfrost-free in an average year

Based on NOAA 1991–2020 records from the Oshkosh, WI weather station, under 1 mile away, elevation 750 ft. Frost can come earlier in low spots and valleys and later near cities and large lakes.

Frost probability by date

Chance of a 32°F frost after the spring date, or before the fall date.

ChanceLast spring frostFirst fall frost
10%May 8Oct 4
20%May 3Oct 9
30%Apr 30Oct 13
40%Apr 28Oct 17
50%Apr 24Oct 20
60%Apr 21Oct 23
70%Apr 18Oct 26
80%Apr 15Oct 30
90%Apr 10Nov 2

Light frost vs. hard freeze

Average (50%) dates for each temperature. Tender plants are damaged at 36°F; most hardy crops survive until 28°F.

TemperatureLast in springFirst in fall
Light frost (36°F)May 4Oct 6
Frost / freeze (32°F)Apr 24Oct 20
Hard freeze (28°F)Apr 13Oct 31

Planting calendar for Oshkosh

Start indoors Plant outside Fall planting
JanFebMarAprMayJunJulAugSepOctNovDec
Tomatoes
Indoors Feb 27 – Mar 13
Transplant May 1 – May 15
Peppers
Indoors Feb 13 – Feb 27
Transplant May 8 – May 22
Eggplant
Indoors Feb 13 – Feb 27
Transplant May 8 – May 22
Basil
Indoors Mar 13 – Mar 27
Transplant May 1 – May 15
Cucumbers
Indoors Mar 27 – Apr 3
Sow or transplant May 1 – May 15
Zucchini and summer squash
Indoors Mar 27 – Apr 3
Sow or transplant May 1 – May 15
Pumpkins and winter squash
Sow May 1 – May 15
Watermelons and melons
Indoors Mar 27 – Apr 3
Sow or transplant May 8 – May 22
Green beans
Sow May 1 – May 15
Sweet corn
Sow May 1 – May 15
Lettuce
Indoors Mar 13 – Mar 27
Sow or transplant Mar 27 – Apr 10
Fall sowing Aug 25 – Sep 22
Spinach
Sow Mar 13 – Apr 3
Fall sowing Aug 25 – Sep 15
Peas
Sow Mar 13 – Mar 27
Fall sowing Aug 11 – Aug 25
Kale
Indoors Feb 27 – Mar 13
Sow or transplant Mar 27 – Apr 10
Fall sowing Aug 11 – Sep 8
Broccoli
Indoors Feb 27 – Mar 13
Transplant Apr 10 – Apr 24
Fall sowing Jul 28 – Aug 11
Cabbage
Indoors Feb 27 – Mar 13
Transplant Apr 3 – Apr 17
Fall sowing Jul 28 – Aug 11
Carrots
Sow Apr 3 – Apr 24
Fall sowing Jul 28 – Aug 11
Radishes
Sow Mar 20 – Apr 10
Fall sowing Sep 8 – Sep 29
Beets
Sow Apr 3 – Apr 24
Fall sowing Aug 11 – Aug 25
Onions (sets or transplants)
Indoors Jan 30 – Feb 13
Plant Mar 27 – Apr 10
Potatoes
Plant Apr 3 – Apr 17
Garlic
Plant Oct 20 – Nov 17

Based on the average last frost (Apr 24) and first frost (Oct 20). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.

Nearby cities

NeenahFond du LacAppletonDe PereManitowocGreen BaySheboyganWest BendAll Wisconsin towns