Median last frost from Apr 6 to Apr 30 across Indiana
NOAA stations
112
Median last frost, Indianapolis
Apr 15
Passed in 9 of 10 years
May 2
Last frost
Last spring frost dates in Indiana
Evansville on the Ohio River reaches its median last frost around Apr 4, Indianapolis around Apr 15, and South Bend near the Michigan line around May 1, almost four weeks apart.
Three dates per station from the NOAA 1991 to 2020 normals. The median is the date half of springs run past. The last column is the date the last 32°F night has passed by in 9 years out of 10, the one to hold tender transplants for.
Lafayette Purdue University AirportLafayette Purdue University Airport, USW00014835
599 ft
Apr 11
Apr 26
May 14
Oct 18
South Bend Michiana Regional AirportSouth Bend Michiana Regional Airport, USW00014848
773 ft
Apr 16
May 1
May 17
Oct 19
Crop chart
When to start seeds in Indiana, spring 2027
Counted back from the median last frost at Indianapolis, April 15. Pick another station to redraw the chart for it.
Start indoorsHarden offSet outSow outdoorsMedian last frostLast freeze passed in 9 of 10 years
Every crop, counted from a median last frost of April 15
Crop
Start indoors
Set out
Sow outdoors
Frost class
Tomato
Feb 25 to Mar 11
Apr 22 to Apr 29
Tender, very tender
Pepper
Feb 18 to Mar 4
Apr 29 to May 6
Tender, very tender
Eggplant
Feb 18 to Mar 4
Apr 29 to May 6
Tender, very tender
Basil
Mar 4 to Mar 18
Apr 29 to May 6
Tender
Celery
Jan 21 to Feb 4
Apr 15 to Apr 22
Tender
Cucumber
Mar 25 to Apr 1
Apr 22 to Apr 29
Apr 15 to Apr 22
Tender
Summer squash
Apr 1 to Apr 8
Apr 29 to May 6
Apr 15 to Apr 22
Tender
Winter squash
Apr 1 to Apr 8
Apr 29 to May 6
Apr 29 to May 6
Tender, very tender
Pumpkin
Apr 1 to Apr 8
Apr 29 to May 6
Apr 29 to May 6
Tender, very tender
Melon (cantaloupe)
Apr 1 to Apr 8
Apr 29 to May 6
Tender, very tender
Watermelon
Mar 25 to Apr 8
Apr 29 to May 6
Tender, very tender
Onion (from seed)
Jan 7 to Jan 21
Mar 18 to Mar 25
Hardy
Leek
Jan 7 to Jan 21
Mar 18 to Mar 25
Hardy
Parsley
Jan 14 to Jan 21
Mar 25 to Apr 1
Half-hardy
Broccoli
Feb 4 to Feb 18
Mar 18 to Apr 1
Hardy
Brussels sprouts
Feb 4 to Feb 18
Mar 18 to Apr 1
Hardy
Cabbage
Feb 4 to Feb 18
Mar 18 to Mar 25
Hardy
Cauliflower
Feb 18 to Mar 4
Apr 1 to Apr 8
Half-hardy
Kale
Feb 4 to Feb 18
Mar 18 to Mar 25
Hardy
Lettuce
Feb 11 to Feb 18
Mar 18 to Mar 25
Hardy
Swiss chard
Feb 18 to Mar 4
Apr 1 to Apr 8
Mar 18 to Mar 25
Half-hardy
Spinach
Jan 21 to Feb 4
Mar 4 to Mar 25
Mar 18 to Apr 1
Hardy
Peas
Mar 18 to Apr 1
Hardy
Radish
Mar 18 to Apr 1
Hardy
Carrot
Apr 1 to Apr 15
Half-hardy
Beet
Apr 1 to Apr 15
Half-hardy
Beans
Apr 15 to Apr 22
Tender
Sweet corn
Apr 15 to Apr 22
Tender
Tomato seedlings at the seed leaf stage, one to a pot. The University of Minnesota Extension holds off on fertilizer until a seedling has several sets of true leaves, then feeds at quarter strength once a week.“Tomato Seedlings (49768696597)” by Amanda Slater from Coventry, West Midlands, UK, CC BY-SA 2.0
Setting out a tomato in June at a community garden. Tender crops go out after the last frost, and after a week or two of hardening off outdoors. “Volunteer planting heirloom tomato (4704185147)”, Pacific Southwest Region 5, Public domain
Seed starting questions for Indiana
Count back from the median last frost where you garden. At Indianapolis (Indianapolis) that date is April 15, so for spring 2027 onions start indoors Jan 7 to Jan 21, peppers Feb 18 to Mar 4 and tomatoes Feb 25 to Mar 11. Across Indiana's 112 NOAA stations the median last frost runs from Apr 6 to Apr 30 for the middle 90 percent, so a garden near Garrett 1 S starts later than one near Evansville Museum.
It depends on the station. The earliest median last spring freeze in Indiana is March 29 at Evansville Museum; the latest is May 2 at Garrett 1 S. A median is a coin flip: at Indianapolis the last 32°F freeze comes after April 15 in half of years, and has passed by May 2 in 9 of 10 years (NOAA 1991 to 2020 normals).
UNH Extension sets tomatoes out 1 to 2 weeks after the last frost, which at Indianapolis is Apr 22 to Apr 29 in 2027. Tomatoes are frost tender, so the date to watch is May 2, when 9 of 10 springs at Indianapolis have had their last 32°F night. Hardening off starts two weeks before setting out (Apr 8 to Apr 22).
UNH Cooperative Extension's method works in any state with a spring frost: "Using a calendar, mark the date and count backwards the number of weeks the seed takes to grow from sowing. This will be the date you will start your seeds." The weeks for each crop come from UNH and Colorado State, and the frost date comes from the NOAA station nearest you in Indiana.
UNH Extension gives 8 to 10 weeks from seed to transplant for both, and sets peppers out 2 weeks after the last frost and eggplant 2 to 3 weeks after, so the sowing date is 6 to 8 weeks before the median last frost. At Indianapolis that is Feb 18 to Mar 4 for peppers.
About two weeks. University of Missouri Extension: "Hardening should be started about two weeks before planting in the garden." University of Minnesota Extension adds that seedlings should go out on a cloudy day or in the late afternoon.
Evansville on the Ohio River reaches its median last frost around Apr 4, Indianapolis around Apr 15, and South Bend near the Michigan line around May 1, almost four weeks apart. Each station carries its own dates: Evansville Apr 4 and South Bend Michiana Regional Airport May 1 at the median.
