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When to plant in Box Elder, SD

USDA Zone 5b

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

In zone 5b, Box Elder gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.

Station · RAPID CITY RGNL AP · 7.8 km
Last spring frost
May 12
50% chance · 32°F
First fall frost
October 1
50% chance · 32°F
Growing season
142 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for Box ElderA year-band showing 32°F frost risk from January to December for Box Elder: last spring frost around May 12, first fall frost around October 1, about 142 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

RAPID CITY RGNL 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 Box Elder’s own odds, recorded at RAPID CITY RGNL AP.

Frost-probability curves for Box ElderProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around May 12 and the first fall frost around October 1, giving about 142 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°FJun 6May 22May 10Sep 7Sep 21Oct 3
32°FMay 26May 12May 1Sep 16Oct 1Oct 14
28°FMay 14May 2Apr 18Sep 26Oct 9Oct 23

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
Broccoli
July 9July 23
Fall sowopen now
Cabbage
July 9July 23
Fall sowopen now
Carrot
July 9July 23
Fall sowopen now
Cauliflower
July 9July 23
Fall sowopen now
Napa Cabbage
July 9August 6
Fall sowin 4 days
Beet
July 23August 6
Fall sowin 4 days
Collards
July 23August 20
Fall sowin 4 days
Endive
July 23August 6
Fall sowin 4 days
Escarole
July 23August 6
Fall sowin 4 days
Fennel (Bulb)
July 23August 6
Fall sowin 4 days
Kale
July 23August 20
Fall sowin 4 days
Kohlrabi
July 23August 20
Fall sowin 4 days
Peas
July 23August 6
Fall sowin 4 days
Radicchio
July 23August 6
Fall sowin 4 days
Swiss Chard
July 23August 6
Fall sowin 4 days
Turnip
July 23August 20
Fall sowin 18 days
Arugula
August 6September 3
Fall sowin 18 days
Bok Choy
August 6August 20
Fall sowin 18 days
Chervil
August 6September 3
Fall sowin 18 days
Cilantro
August 6September 3
Fall sowin 18 days
Claytonia (Miner's Lettuce)
August 6September 3
Fall sowin 18 days
Corn Salad (Mâche)
August 6September 3
Fall sowin 18 days
Gai Lan (Chinese Broccoli)
August 6August 20
Fall sowin 18 days
Lettuce
August 6September 3
Fall sowin 18 days
Mizuna
August 6September 3
Fall sowin 18 days
Mustard Greens
August 6September 3
Fall sowin 18 days
Radish
August 6September 3
Fall sowin 18 days
Shungiku (Edible Chrysanthemum)
August 6August 20
Fall sowin 18 days
Spinach
August 6September 3
Fall sowin 18 days
Tatsoi
August 6September 3

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 Box Elder, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 16 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.

RAPID CITY RGNL AP
Primary
8 km · 963 m elevation
SPRING
May 12
FALL
Oct 1
RAPID CITY WFO
11 km · 1030 m elevation
SPRING
May 3
FALL
Oct 8
RAPID CITY 4NW
16 km · 1060 m elevation
SPRING
May 10
FALL
Oct 5

Box Elder planting FAQ

When is the last spring frost in Box Elder, SD?

On average, the last spring frost in Box Elder is around May 12 (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 Box Elder, SD?

The first fall frost in Box Elder typically arrives around October 1 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Box Elder in?

Box Elder 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 Box Elder?

Box Elder has about 142 frost-free days — a short growing season — between the average last spring frost (May 12) and first fall frost (October 1).

When should I plant tomatoes in Box Elder?

For Box Elder, sow tomatoes indoors about March 17–March 31 and move the seedlings out around May 19, after the last spring frost.

Planting reminders

Never miss a window in Box Elder

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

Nearby cities

8 within reach

Frost dates recorded at RAPID CITY RGNL AP, 8 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 Box Elder, SD — Frost Dates & Zone 5b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00024090. Retrieved from https://blissgarden.com/south-dakota/box-elder.