Frost Dates for Buffalo Grove, IL

In Buffalo Grove, IL, the average last spring frost is around Apr 19 and the average first fall frost around Oct 26, for a growing season of about 190 days. For frost-tender plants, wait until May 3, when the chance of frost drops to 10%.

Average last frostApr 1950% chance of frost after this date
Safe to plantMay 3only a 10% chance of frost after
Average first frostOct 2650% chance of frost before this date
Growing season190 daysfrost-free in an average year

Based on NOAA 1991–2020 records from the Chicago Palwaukee Airport, IL weather station, 4 miles away, elevation 636 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 3Oct 13
20%Apr 28Oct 18
30%Apr 25Oct 22
40%Apr 22Oct 24
50%Apr 19Oct 26
60%Apr 16Oct 29
70%Apr 13Oct 31
80%Apr 9Nov 4
90%Apr 4Nov 9

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)Apr 30Oct 16
Frost / freeze (32°F)Apr 19Oct 26
Hard freeze (28°F)Apr 5Nov 7

Planting calendar for Buffalo Grove

Start indoors Plant outside Fall planting
JanFebMarAprMayJunJulAugSepOctNovDec
Tomatoes
Indoors Feb 22 – Mar 8
Transplant Apr 26 – May 10
Peppers
Indoors Feb 8 – Feb 22
Transplant May 3 – May 17
Eggplant
Indoors Feb 8 – Feb 22
Transplant May 3 – May 17
Basil
Indoors Mar 8 – Mar 22
Transplant Apr 26 – May 10
Cucumbers
Indoors Mar 22 – Mar 29
Sow or transplant Apr 26 – May 10
Zucchini and summer squash
Indoors Mar 22 – Mar 29
Sow or transplant Apr 26 – May 10
Pumpkins and winter squash
Sow Apr 26 – May 10
Watermelons and melons
Indoors Mar 22 – Mar 29
Sow or transplant May 3 – May 17
Green beans
Sow Apr 26 – May 10
Sweet corn
Sow Apr 26 – May 10
Lettuce
Indoors Mar 8 – Mar 22
Sow or transplant Mar 22 – Apr 5
Fall sowing Aug 31 – Sep 28
Spinach
Sow Mar 8 – Mar 29
Fall sowing Aug 31 – Sep 21
Peas
Sow Mar 8 – Mar 22
Fall sowing Aug 17 – Aug 31
Kale
Indoors Feb 22 – Mar 8
Sow or transplant Mar 22 – Apr 5
Fall sowing Aug 17 – Sep 14
Broccoli
Indoors Feb 22 – Mar 8
Transplant Apr 5 – Apr 19
Fall sowing Aug 3 – Aug 17
Cabbage
Indoors Feb 22 – Mar 8
Transplant Mar 29 – Apr 12
Fall sowing Aug 3 – Aug 17
Carrots
Sow Mar 29 – Apr 19
Fall sowing Aug 3 – Aug 17
Radishes
Sow Mar 15 – Apr 5
Fall sowing Sep 14 – Oct 5
Beets
Sow Mar 29 – Apr 19
Fall sowing Aug 17 – Aug 31
Onions (sets or transplants)
Indoors Jan 25 – Feb 8
Plant Mar 22 – Apr 5
Potatoes
Plant Mar 29 – Apr 12
Garlic
Plant Oct 26 – Nov 23

Based on the average last frost (Apr 19) and first frost (Oct 26). The dashed lines mark those dates. Seed packets list days to maturity; adjust for your varieties.

Nearby cities

WheelingVernon HillsArlington HeightsPalatineNorthbrookMount ProspectHighland ParkMundeleinAll Illinois towns