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When to plant in Cedar Rapids, IA

USDA Zone 5b

Here are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Cedar Rapids, Iowa — all computed from Cedar Rapids's nearest NOAA weather station.

Zone 5b means Cedar Rapids sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.

Station · CEDAR RAPIDS MUNI AP · 9.5 km
Last spring frost
April 27
50% chance · 32°F
First fall frost
October 11
50% chance · 32°F
Growing season
167 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Cedar RapidsA year-band showing 32°F frost risk from January to December for Cedar Rapids: last spring frost around April 27, first fall frost around October 11, about 167 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average first fall frost in Cedar Rapids is now 5 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

CEDAR RAPIDS MUNI AP · 1991–2020

The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Cedar Rapids’s own odds, recorded at CEDAR RAPIDS MUNI AP.

Frost-probability curves for Cedar RapidsProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 27 and the first fall frost around October 11, giving about 167 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FMay 20May 6Apr 23Sep 16Oct 1Oct 14
32°FMay 11Apr 27Apr 13Sep 25Oct 11Oct 23
28°FMay 1Apr 16Apr 3Oct 7Oct 21Nov 1

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19
Fall sowopen now
Rutabaga
July 5July 19
Fall sowopen now
Broccoli
July 19August 2
Fall sowopen now
Cabbage
July 19August 2
Fall sowopen now
Carrot
July 19August 2
Fall sowopen now
Cauliflower
July 19August 2
Fall sowopen now
Napa Cabbage
July 19August 16
Fall sowin 14 days
Beet
August 2August 16
Fall sowin 14 days
Collards
August 2August 30
Fall sowin 14 days
Endive
August 2August 16
Fall sowin 14 days
Escarole
August 2August 16
Fall sowin 14 days
Fennel (Bulb)
August 2August 16
Fall sowin 14 days
Kale
August 2August 30
Fall sowin 14 days
Kohlrabi
August 2August 30
Fall sowin 14 days
Peas
August 2August 16
Fall sowin 14 days
Radicchio
August 2August 16
Fall sowin 14 days
Swiss Chard
August 2August 16
Fall sowin 14 days
Turnip
August 2August 30
Fall sowin 28 days
Arugula
August 16September 13
Fall sowin 28 days
Bok Choy
August 16August 30
Fall sowin 28 days
Chervil
August 16September 13
Fall sowin 28 days
Cilantro
August 16September 13
Fall sowin 28 days
Claytonia (Miner's Lettuce)
August 16September 13
Fall sowin 28 days
Corn Salad (Mâche)
August 16September 13
Fall sowin 28 days
Gai Lan (Chinese Broccoli)
August 16August 30
Fall sowin 28 days
Lettuce
August 16September 13
Fall sowin 28 days
Mizuna
August 16September 13
Fall sowin 28 days
Mustard Greens
August 16September 13
Fall sowin 28 days
Radish
August 16September 13
Fall sowin 28 days
Shungiku (Edible Chrysanthemum)
August 16August 30
Fall sowin 28 days
Spinach
August 16September 13
Fall sowin 28 days
Tatsoi
August 16September 13

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in Cedar Rapids, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 34 km · complete 32°F normals

When stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.

CEDAR RAPIDS MUNI AP
Primary
10 km · 265 m elevation
SPRING
Apr 27
FALL
Oct 11
CEDAR RAPIDS #1
12 km · 248 m elevation
SPRING
Apr 28
FALL
Oct 12
ANAMOSA 3 SSW
34 km · 276 m elevation
SPRING
Apr 27
FALL
Oct 13

Cedar Rapids planting FAQ

When is the last spring frost in Cedar Rapids, IA?

On average, the last spring frost in Cedar Rapids is around April 27 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.

When is the first fall frost in Cedar Rapids, IA?

Expect Cedar Rapids's first fall frost near October 11 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Cedar Rapids in?

Cedar Rapids is in USDA hardiness zone 5b. In zone 5b, winters are cold — pick cold-hardy varieties and protect tender crops.

How long is the growing season in Cedar Rapids?

There are roughly 167 frost-free days in Cedar Rapids (a moderate growing season), running from the average last frost around April 27 to the first fall frost near October 11.

When should I plant tomatoes in Cedar Rapids?

In Cedar Rapids, start tomato seeds indoors around March 2–March 16, then transplant seedlings outdoors around May 4 once the danger of frost has passed.

Planting reminders

Never miss a window in Cedar Rapids

An email when it’s time to start seeds, transplant, and sow — timed to Cedar Rapids’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at CEDAR RAPIDS MUNI AP, 10 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in Cedar Rapids, IA — Frost Dates & Zone 5b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00014990. Retrieved from https://blissgarden.com/iowa/cedar-rapids.
When to Plant in Cedar Rapids, IA — Frost Dates & Zone 5b — BlissGarden