Last frost date in Merrillville, IN

Average last frost
April 22

Expect the last frost in Merrillville around April 22. Frost after May 6 happens in only one year out of ten. The first fall frost usually arrives about October 25, which leaves 185 frost-free days. An early freeze before October 12 happens one year in ten.

Safe after (10% risk)
May 6
Average first frost
Oct 25
Frost-free season
185 days
Hard freeze (28°F) ends
Apr 9
Next 7 nights in Merrillville

No frost in the next 7 nights

National Weather Service forecast, updated Oct 22, 12:57 UTC

  1. ThuOct 2244°
  2. FriOct 2345°
  3. SatOct 2448°
  4. SunOct 2550°
  5. MonOct 2648°
  6. TueOct 2745°
  7. WedOct 2846°
JanFebMarAprMayJunJulAugSepOctNovDecLast frost Apr 22First frost Oct 25185 frost-free daysBlue: chance of 32°F frost. Green: average frost-free season.JFMAMJJASOND185 frost-free days
Frost risk through the year at Valparaiso Wtr Wks, 14.8 miles from Merrillville.

Planting calendar for Merrillville

Windows count forward or back from the average frost dates above. Click a crop for dates across Indiana.

Start indoorsPlant outSow outdoorsFall plantingAverage last and first frost
Warm-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
TomatoesApr 29–May 13
PumpkinsMay 6–May 20
SunflowersApr 22–May 13
CucumbersMay 6–May 13
CornApr 29–May 13
Sweet potatoesMay 13–May 27
WatermelonMay 6–May 20
Green beansApr 29–May 20
ZucchiniApr 29–May 13
OkraMay 13–May 27
PeppersMay 6–May 20
BasilApr 29–May 13
Butternut squashApr 29–May 13
CantaloupeMay 6–May 20
EggplantMay 6–May 20
Cool-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
PotatoesMar 25–Apr 8
OnionsMar 11–Apr 1
CarrotsApr 1–May 6
LettuceApr 8–Apr 29
BroccoliMar 25–Apr 8
BeetsMar 25–May 6
PeasMar 11–Mar 25
CabbageMar 25–Apr 8
RadishesMar 18–Apr 29
Brussels sproutsApr 8–Apr 22
SpinachMar 11–Apr 1
CilantroApr 8–Apr 29
KaleMar 25–Apr 8
Collard greensMar 25–Apr 8
TurnipsMar 25–Apr 8
DillApr 22–May 6
CeleryApr 29–May 6
CauliflowerApr 8–Apr 22
LeeksApr 8–Apr 22
Swiss chardApr 8–May 6
ParsleyApr 8–Apr 29
Fall bulbs and garlic
JanFebMarAprMayJunJulAugSepOctNovDec
Tulip bulbsOct 11–Nov 15
GarlicOct 4–Nov 8
Daffodil bulbsSep 27–Nov 8
Perennials
JanFebMarAprMayJunJulAugSepOctNovDec
StrawberriesMar 25–Apr 8
AsparagusMar 25–Apr 8

Frost probabilities

ThresholdSpring, 90% chance laterSpring, 50%Spring, 10%Fall, 10% chance earlierFall, 50%Fall, 90%
Light frost, 32°FApr 7Apr 22May 6Oct 12Oct 25Nov 6
Hard freeze, 28°FMar 25Apr 9Apr 24Oct 24Nov 5Nov 21

Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.

Where these numbers come from

NOAA station Valparaiso Wtr Wks (USC00128999) sits 14.8 miles from the center of Merrillville at 800 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.

Questions

When is the last frost in Merrillville, IN?

The average last frost date in Merrillville is April 22, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 6.

When is the first frost in Merrillville?

The first frost in fall usually comes around October 25. One year in ten it arrives before October 12.

How long is the growing season in Merrillville?

About 185 days between the average last and first frost.

When should I plant tomatoes in Merrillville?

Plant tomato seedlings outside from April 29 to May 13. Start seeds indoors six to eight weeks earlier.

Nearby in Indiana

All 49 cities in Indiana