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When to plant in London, OH

USDA Zone 6a

Everything below — frost dates, hardiness zone, and what to plant when in London, Ohio — is derived from the closest NOAA station with complete climate normals.

Zone 6a means London sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.

Station · LONDON FISH HATCHERY · 6.1 km
Last spring frost
April 24
50% chance · 32°F
First fall frost
October 18
50% chance · 32°F
Growing season
177 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for LondonA year-band showing 32°F frost risk from January to December for London: last spring frost around April 24, first fall frost around October 18, about 177 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average first fall frost in London is now 9 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

LONDON FISH HATCHERY · 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 London’s own odds, recorded at LONDON FISH HATCHERY.

Frost-probability curves for LondonProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 24 and the first fall frost around October 18, giving about 177 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 4Apr 20Sep 23Oct 7Oct 20
32°FMay 10Apr 24Apr 10Oct 5Oct 18Nov 1
28°FApr 30Apr 14Mar 31Oct 15Oct 29Nov 12

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 12July 26
Fall sowin 7 days
Broccoli
July 26August 9
Fall sowin 7 days
Cabbage
July 26August 9
Fall sowin 7 days
Carrot
July 26August 9
Fall sowin 7 days
Cauliflower
July 26August 9
Fall sowin 7 days
Napa Cabbage
July 26August 23
Fall sowin 21 days
Beet
August 9August 23
Fall sowin 21 days
Collards
August 9September 6
Fall sowin 21 days
Endive
August 9August 23
Fall sowin 21 days
Escarole
August 9August 23
Fall sowin 21 days
Fennel (Bulb)
August 9August 23
Fall sowin 21 days
Kale
August 9September 6
Fall sowin 21 days
Kohlrabi
August 9September 6
Fall sowin 21 days
Peas
August 9August 23
Fall sowin 21 days
Radicchio
August 9August 23
Fall sowin 21 days
Swiss Chard
August 9August 23
Fall sowin 21 days
Turnip
August 9September 6

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

Nearby weather stations

3 within 37 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.

LONDON FISH HATCHERY
Primary
6 km · 341 m elevation
SPRING
Apr 24
FALL
Oct 18
SPRINGFIELD WTP
33 km · 290 m elevation
SPRING
Apr 25
FALL
Oct 19
MARYSVILLE
37 km · 296 m elevation
SPRING
Apr 19
FALL
Oct 26

London planting FAQ

When is the last spring frost in London, OH?

London's average last spring frost falls near April 24 — 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 London, OH?

In London, the first 32°F freeze of fall lands around October 18 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is London in?

London is in USDA hardiness zone 6a. In zone 6a, winters are moderate — most common vegetables grow well in season.

How long is the growing season in London?

There are roughly 177 frost-free days in London (a moderate growing season), running from the average last frost around April 24 to the first fall frost near October 18.

When should I plant tomatoes in London?

In London, start tomato seeds indoors around February 27–March 13, then transplant seedlings outdoors around May 1 once the danger of frost has passed.

Planting reminders

Never miss a window in London

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

Nearby cities

8 within reach

Frost dates recorded at LONDON FISH HATCHERY, 6 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 London, OH — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00334681. Retrieved from https://blissgarden.com/ohio/london.