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When to plant in Delaware, OH

USDA Zone 6b

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

These dates come from a station roughly 19 km away, the closest with full normals; terrain around Delaware (elevation, water, pavement) can move your real frost dates a few days either way. In zone 6b, Delaware gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.

Station · MARYSVILLE · 19.3 km
Last spring frost
April 19
50% chance · 32°F
First fall frost
October 26
50% chance · 32°F
Growing season
190 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for DelawareA year-band showing 32°F frost risk from January to December for Delaware: last spring frost around April 19, first fall frost around October 26, about 190 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

MARYSVILLE · 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 Delaware’s own odds, recorded at MARYSVILLE.

Frost-probability curves for DelawareProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 19 and the first fall frost around October 26, giving about 190 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 15Apr 30Apr 17Sep 30Oct 14Oct 27
32°FMay 5Apr 19Apr 5Oct 13Oct 26Nov 7
28°FApr 22Apr 7Mar 23Oct 25Nov 6Nov 21

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 6July 20
Fall sowin 1 days
Rutabaga
July 20August 3
Fall sowin 15 days
Broccoli
August 3August 17
Fall sowin 15 days
Cabbage
August 3August 17
Fall sowin 15 days
Carrot
August 3August 17
Fall sowin 15 days
Cauliflower
August 3August 17
Fall sowin 15 days
Napa Cabbage
August 3August 31

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

Nearby weather stations

3 within 23 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.

MARYSVILLE
Primary
19 km · 296 m elevation
SPRING
Apr 19
FALL
Oct 26
WESTERVILLE
21 km · 244 m elevation
SPRING
Apr 22
FALL
Oct 24
COLUMBUS OHIO STATE UNIV AP
23 km · 276 m elevation
SPRING
Apr 22
FALL
Oct 23

Delaware planting FAQ

When is the last spring frost in Delaware, OH?

Plan for the last spring frost in Delaware around April 19 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.

When is the first fall frost in Delaware, OH?

Expect Delaware's first fall frost near October 26 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Delaware in?

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

How long is the growing season in Delaware?

Delaware has about 190 frost-free days — a moderate growing season — between the average last spring frost (April 19) and first fall frost (October 26).

When should I plant tomatoes in Delaware?

For Delaware, sow tomatoes indoors about February 22–March 8 and move the seedlings out around April 26, after the last spring frost.

Planting reminders

Never miss a window in Delaware

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

Nearby cities

8 within reach

Frost dates recorded at MARYSVILLE, 19 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 Delaware, OH — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00334979. Retrieved from https://blissgarden.com/ohio/delaware.
When to Plant in Delaware, OH — Frost Dates & Zone 6b — BlissGarden