Frost Dates for Manitowoc, WI

In Manitowoc, WI, the average last spring frost is around Apr 30 and the average first fall frost around Oct 20, for a growing season of about 171 days. For frost-tender plants, wait until May 15, when the chance of frost drops to 10%.

Average last frostApr 3050% chance of frost after this date
Safe to plantMay 15only a 10% chance of frost after
Average first frostOct 2050% chance of frost before this date
Growing season171 daysfrost-free in an average year

Based on NOAA 1991–2020 records from the Manitowoc, WI weather station, 2 miles away, elevation 584 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 15Oct 3
20%May 10Oct 8
30%May 6Oct 13
40%May 2Oct 17
50%Apr 30Oct 20
60%Apr 26Oct 23
70%Apr 23Oct 27
80%Apr 19Oct 30
90%Apr 14Nov 3

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 12Oct 7
Frost / freeze (32°F)Apr 30Oct 20
Hard freeze (28°F)Apr 16Nov 1

Planting calendar for Manitowoc

Start indoors Plant outside Fall planting
JanFebMarAprMayJunJulAugSepOctNovDec
Tomatoes
Indoors Mar 5 – Mar 19
Transplant May 7 – May 21
Peppers
Indoors Feb 19 – Mar 5
Transplant May 14 – May 28
Eggplant
Indoors Feb 19 – Mar 5
Transplant May 14 – May 28
Basil
Indoors Mar 19 – Apr 2
Transplant May 7 – May 21
Cucumbers
Indoors Apr 2 – Apr 9
Sow or transplant May 7 – May 21
Zucchini and summer squash
Indoors Apr 2 – Apr 9
Sow or transplant May 7 – May 21
Pumpkins and winter squash
Sow May 7 – May 21
Watermelons and melons
Indoors Apr 2 – Apr 9
Sow or transplant May 14 – May 28
Green beans
Sow May 7 – May 21
Sweet corn
Sow May 7 – May 21
Lettuce
Indoors Mar 19 – Apr 2
Sow or transplant Apr 2 – Apr 16
Fall sowing Aug 25 – Sep 22
Spinach
Sow Mar 19 – Apr 9
Fall sowing Aug 25 – Sep 15
Peas
Sow Mar 19 – Apr 2
Fall sowing Aug 11 – Aug 25
Kale
Indoors Mar 5 – Mar 19
Sow or transplant Apr 2 – Apr 16
Fall sowing Aug 11 – Sep 8
Broccoli
Indoors Mar 5 – Mar 19
Transplant Apr 16 – Apr 30
Fall sowing Jul 28 – Aug 11
Cabbage
Indoors Mar 5 – Mar 19
Transplant Apr 9 – Apr 23
Fall sowing Jul 28 – Aug 11
Carrots
Sow Apr 9 – Apr 30
Fall sowing Jul 28 – Aug 11
Radishes
Sow Mar 26 – Apr 16
Fall sowing Sep 8 – Sep 29
Beets
Sow Apr 9 – Apr 30
Fall sowing Aug 11 – Aug 25
Onions (sets or transplants)
Indoors Feb 5 – Feb 19
Plant Apr 2 – Apr 16
Potatoes
Plant Apr 9 – Apr 23
Garlic
Plant Oct 20 – Nov 17

Based on the average last frost (Apr 30) and first frost (Oct 20). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.

Nearby cities

SheboyganDe PereGreen BayAppletonNeenahFond du LacOshkoshWest BendAll Wisconsin towns