Frost dates · USDA zone 5b

Frost dates for Urbandale, IA

Urbandale, IA sees its last 32 °F night of spring around April 18 and its first of fall around October 20 — a 184-day freeze-free season in a typical year.

Apr 18Last spring frostmedian · 1 in 10 years after May 2
Oct 20First fall frostmedian · 1 in 10 years before Oct 4
184Freeze-free daysmedian year · ≥165 in 9 of 10
5bUSDA zone2023 map · ZIP 50325
Build a Urbandale sauce plan →

Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.

Freeze odds, by date

OddsLast spring freeze afterFirst fall freeze before
9 years in 10Apr 4Nov 1
Median — 1 year in 2Apr 18Oct 20
1 year in 10May 2Oct 4

The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 184 days median, at least 165 in 9 years of 10, at least 203 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of Apr 8 and first of Oct 30.

Urbandale planting calendar, 2027

Every row runs from the median last frost (Apr 18) and median first frost (Oct 20) above, using each cultivar's days to maturity. Same engine as the Plan Builder.

CropStart indoorsTransplant / plantFirst harvestDays
Hardneck GarlicSiberian (porcelain hardneck)—Oct 15prior fallJun 12240 from sow
Spanish OnionYellow Sweet Spanish (long-day)Jan 24Mar 21Jul 9110 from transplant
Mustard greensGarnet Giant (Brassica juncea)Direct sowApr 18May 1830 from sow
CilantroSlow Bolt (Coriandrum sativum)Apr 4Apr 4May 1945 from sow
Genovese BasilGenoveseMar 21May 2Jul 160 from transplant
CayenneLong Slim Cayenne (Capsicum annuum)Feb 21Apr 25Jul 975 from transplant
HabaneroOrange Habanero (Capsicum chinense)Feb 7May 2Aug 595 from transplant
JalapeñoEarly Jalapeño (Capsicum annuum)Feb 21Apr 25Jul 975 from transplant
Marconi Red PepperMarconi Red (Capsicum annuum)Feb 21Apr 25Jul 1480 from transplant
SerranoSerrano Tampiqueño (Capsicum annuum)Feb 21Apr 25Jul 1480 from transplant
Nantes CarrotScarlet NantesApr 4Apr 4Jun 1370 from sow
TomatilloToma VerdeMar 7Apr 25Jul 470 from transplant
Roma TomatoRoma VF (determinate paste)Mar 7Apr 25Jul 975 from transplant
San Marzano TomatoSan Marzano (indeterminate paste)Mar 7Apr 25Jul 1480 from transplant

Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.

Urbandale frost questions

When is the last frost in Urbandale, IA?

The median last 32 °F freeze at DES MOINES INTL AP, IA is April 18: half of years see a later one. One year in ten, a freeze still comes after May 2; nine years in ten, it comes after April 4. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.

When is the first frost in Urbandale, IA?

The median first 32 °F freeze of fall is October 20. One year in ten it arrives before October 4; nine years in ten, before November 1.

How long is the growing season in Urbandale, IA?

184 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 165 days; one year in ten, at least 203 days.

What growing zone is Urbandale, IA?

USDA hardiness zone 5b, per the 2023 USDA Plant Hardiness Zone Map for ZIP 50325. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.

When should I plant tomatoes in Urbandale, IA?

Start Roma VF (determinate paste) seeds indoors around Mar 7 and transplant around Apr 25, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for May 2. First ripe fruit lands around Jul 9.

When should I plant peppers in Urbandale, IA?

Sow jalapeño indoors on a heat mat around Feb 21; transplant no earlier than Apr 25, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Jul 9.

Nearby in Iowa

All Iowa frost dates → · How frost-date math drives a sowing calendar →