FrostDateByZip

Frost dates for 37409Chattanooga, TN

The average last spring frost in Chattanooga is March 24 and the average first fall frost is November 9, giving a typical growing season of about 230 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Mar 24

Safer after Apr 8 (1-in-10 risk)

Average first fall frost
Nov 9

Possible by Oct 27 (1-in-10 risk)

Growing season
230 days

First frost typically in 6 days

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
TemperatureLast spring: 90% / 50% / 10% chanceFirst fall: 10% / 50% / 90% chanceGrowing season (50%)Years with at least one
Light frost (36°F)Mar 19 · Apr 4 · Apr 20Oct 19 · Oct 31 · Nov 11208 days100%
Frost / freeze (32°F)Mar 6 · Mar 24 · Apr 8Oct 27 · Nov 9 · Nov 26230 days100%
Hard freeze (28°F)Feb 18 · Mar 11 · Mar 30Nov 6 · Nov 22 · Dec 13257 days100%

Planting calendar for Chattanooga

Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.

CropTaskWindow
TomatoesStart seeds indoorsFeb 21 – Apr 29
TomatoesTransplant outdoorsApr 9 – Jul 20
PeppersStart seeds indoorsFeb 21 – Mar 24
PeppersTransplant outdoorsApr 23 – May 24
EggplantStart seeds indoorsMar 10 – Apr 8
EggplantTransplant outdoorsApr 23 – May 24
CucumbersSow outdoorsApr 23 – Jul 30
Summer squashSow outdoorsApr 9 – May 24
Winter squash & pumpkinsSow outdoorsApr 23 – May 24
Snap beansSow outdoorsApr 9 – Aug 22
Sweet cornSow outdoorsApr 9 – Jul 20
Watermelon & cantaloupeSow outdoorsApr 23 – May 24
OkraSow outdoorsApr 16 – May 9
PeasSow outdoors (spring)Feb 21 – Apr 8
PotatoesPlant outdoors (spring)Feb 21 – Apr 23
OnionsStart seeds indoors (spring)Jan 10 – Feb 6
OnionsTransplant outdoors (spring)Mar 10 – Apr 8
BroccoliStart seeds indoors (spring)Feb 3 – Mar 9
BroccoliTransplant outdoors (spring)Mar 10 – Apr 8
BroccoliStart seeds indoors (fall)Jul 10 – Jul 20
BroccoliTransplant outdoors (fall)Aug 9 – Aug 20
CabbageStart seeds indoors (spring)Jan 24 – Feb 21
CabbageTransplant outdoors (spring)Feb 21 – Mar 24
CabbageStart seeds indoors (fall)Jun 30 – Jul 30
CabbageTransplant outdoors (fall)Jul 30 – Aug 30
Leaf lettuceSow outdoors (spring)Feb 21 – May 9
Leaf lettuceSow outdoors (fall)Jul 30 – Sep 15
SpinachSow outdoors (spring)Feb 14 – Mar 30
SpinachSow outdoors (fall)Aug 16 – Sep 20
RadishesSow outdoors (spring)Feb 21 – Apr 13
RadishesSow outdoors (fall)Jul 30 – Sep 30
KaleSow outdoors (spring)Mar 10 – Mar 30
KaleSow outdoors (fall)Jul 23 – Aug 30
CarrotsSow outdoors (spring)Mar 24 – May 9
CarrotsSow outdoors (fall)Jun 30 – Aug 15
GarlicPlant outdoors (fall)Oct 30 – Nov 30

Where these dates come from

ZIP code 37409 is matched to the NOAA station Chattanooga Lovell Ap, TN, 12.4 km away, at 671 ft elevation (100 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Chattanooga Lovell Ap, TN (used)671 ftMar 24Nov 9
Lookout Mtn-Point Park, TN2,110 ftMar 31Nov 6
Chickamauga Pk Larc, GA782 ftApr 6Oct 30
Chickamauga 2 Sw, GA799 ftMar 25Nov 9

Frost dates near Chattanooga

Frequently asked questions

When is the last frost in Chattanooga, TN?
For ZIP code 37409, the average last spring frost (32°F) is March 24, based on NOAA 1991-2020 climate normals for the Chattanooga Lovell Ap, TN weather station. There is a 1-in-10 chance of a frost after April 8.
When is the first frost in Chattanooga, TN?
The average first fall frost (32°F) is November 9. There is a 1-in-10 chance of frost by October 27, so tender plants are at risk from that point on.
How long is the growing season in 37409?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 230 days long.
Are these frost dates a forecast?
No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.