Last frost date in Dubuque, IA
In Dubuque, the last spring frost comes around April 19 in an average year. Wait until May 4 if you want 90% odds of no more frost. The first fall frost usually arrives about October 21, which leaves 184 frost-free days. An early freeze before October 7 happens one year in ten.
- Safe after (10% risk)
- May 4
- Average first frost
- Oct 21
- Frost-free season
- 184 days
- Hard freeze (28°F) ends
- Apr 7
No frost in the next 7 nights
Later than usual: the average first frost here is October 21.
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2252°
- FriOct 2354°
- SatOct 2453°
- SunOct 2551°
- MonOct 2646°
- TueOct 2743°
- WedOct 2844°
Planting calendar for Dubuque
Windows count forward or back from the average frost dates above. Click a crop for dates across Iowa.
TomatoesApr 26–May 10
PumpkinsMay 3–May 17
SunflowersApr 19–May 10
CucumbersMay 3–May 10
CornApr 26–May 10
Sweet potatoesMay 10–May 24
WatermelonMay 3–May 17
Green beansApr 26–May 17
ZucchiniApr 26–May 10
OkraMay 10–May 24
PeppersMay 3–May 17
BasilApr 26–May 10
Butternut squashApr 26–May 10
CantaloupeMay 3–May 17
EggplantMay 3–May 17
PotatoesMar 22–Apr 5
OnionsMar 8–Mar 29
CarrotsMar 29–May 3
LettuceApr 5–Apr 26
BroccoliMar 22–Apr 5
BeetsMar 22–May 3
PeasMar 8–Mar 22
CabbageMar 22–Apr 5
RadishesMar 15–Apr 26
Brussels sproutsApr 5–Apr 19
SpinachMar 8–Mar 29
CilantroApr 5–Apr 26
KaleMar 22–Apr 5
Collard greensMar 22–Apr 5
TurnipsMar 22–Apr 5
DillApr 19–May 3
CeleryApr 26–May 3
CauliflowerApr 5–Apr 19
LeeksApr 5–Apr 19
Swiss chardApr 5–May 3
ParsleyApr 5–Apr 26
Tulip bulbsOct 7–Nov 11
GarlicSep 30–Nov 4
Daffodil bulbsSep 23–Nov 4
StrawberriesMar 22–Apr 5
AsparagusMar 22–Apr 5Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 4 | Apr 19 | May 4 | Oct 7 | Oct 21 | Nov 2 |
| Hard freeze, 28°F | Mar 25 | Apr 7 | Apr 22 | Oct 19 | Nov 1 | Nov 14 |
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 Dubuque L&d 11 (USC00132364) sits 4.2 miles from the center of Dubuque at 620 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 Dubuque, IA?
The average last frost date in Dubuque is April 19, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 4.
When is the first frost in Dubuque?
The first frost in fall usually comes around October 21. One year in ten it arrives before October 7.
How long is the growing season in Dubuque?
About 184 days between the average last and first frost.
When should I plant tomatoes in Dubuque?
Plant tomato seedlings outside from April 26 to May 10. Start seeds indoors six to eight weeks earlier.
Nearby in Iowa
- ClintonApr 22
- MarionApr 28
- Cedar RapidsApr 27
- DavenportApr 19
- BettendorfApr 16
- North LibertyApr 21
- CoralvilleApr 21
- Iowa CityApr 21
- MuscatineApr 24
- WaterlooApr 27
- Cedar FallsApr 27
- MarshalltownApr 28