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When to plant in Mehlville, MO

USDA Zone 7a

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

Zone 7a means many perennials and even some tender shrubs overwinter in Mehlville, while your frost dates still decide when annuals go out.

Station · CAHOKIA · 12.7 km
Last spring frost
April 6
50% chance · 32°F
First fall frost
October 27
50% chance · 32°F
Growing season
204 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for MehlvilleA year-band showing 32°F frost risk from January to December for Mehlville: last spring frost around April 6, first fall frost around October 27, about 204 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

CAHOKIA · 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 Mehlville’s own odds, recorded at CAHOKIA.

Frost-probability curves for MehlvilleProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 6 and the first fall frost around October 27, giving about 204 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 3Apr 18Apr 4Oct 5Oct 18Oct 28
32°FApr 20Apr 6Mar 22Oct 14Oct 27Nov 7
28°FApr 10Mar 27Mar 11Oct 25Nov 5Nov 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
Brussels Sprouts
July 7July 21
Fall sowin 2 days
Rutabaga
July 21August 4
Fall sowin 16 days
Broccoli
August 4August 18
Fall sowin 16 days
Cabbage
August 4August 18
Fall sowin 16 days
Carrot
August 4August 18
Fall sowin 16 days
Cauliflower
August 4August 18
Fall sowin 16 days
Napa Cabbage
August 4September 1

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 Mehlville, 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.

CAHOKIA
Primary
13 km · 122 m elevation
SPRING
Apr 6
FALL
Oct 27
ST LOUIS SCI CTR
15 km · 157 m elevation
SPRING
Apr 1
FALL
Nov 4
CAHOKIA ST LOUIS AP
16 km · 126 m elevation
SPRING
Apr 8
FALL
Oct 26

Mehlville planting FAQ

When is the last spring frost in Mehlville, MO?

Mehlville's average last spring frost falls near April 6 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.

When is the first fall frost in Mehlville, MO?

In Mehlville, the first 32°F freeze of fall lands around October 27 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Mehlville in?

Mehlville is in USDA hardiness zone 7a. In zone 7a, winters are moderate — most common vegetables grow well in season.

How long is the growing season in Mehlville?

There are roughly 204 frost-free days in Mehlville (a moderate growing season), running from the average last frost around April 6 to the first fall frost near October 27.

When should I plant tomatoes in Mehlville?

In Mehlville, start tomato seeds indoors around February 9–February 23, then transplant seedlings outdoors around April 13 once the danger of frost has passed.

Planting reminders

Never miss a window in Mehlville

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

Nearby cities

8 within reach

Frost dates recorded at CAHOKIA, 13 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 Mehlville, MO — Frost Dates & Zone 7a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00111160. Retrieved from https://blissgarden.com/missouri/mehlville.
When to Plant in Mehlville, MO — Frost Dates & Zone 7a — BlissGarden