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When to plant in Bethesda, MD

USDA Zone 7b

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

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

Station · DALECARLIA RSVR · 5.4 km
Last spring frost
April 9
50% chance · 32°F
First fall frost
October 31
50% chance · 32°F
Growing season
205 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for BethesdaA year-band showing 32°F frost risk from January to December for Bethesda: last spring frost around April 9, first fall frost around October 31, about 205 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

DALECARLIA RSVR · 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 Bethesda’s own odds, recorded at DALECARLIA RSVR.

Frost-probability curves for BethesdaProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around April 9 and the first fall frost around October 31, giving about 205 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 10Apr 23Apr 8Oct 7Oct 20Nov 2
32°FApr 26Apr 9Mar 27Oct 16Oct 31Nov 13
28°FApr 12Mar 30Mar 12Oct 29Nov 9Nov 27

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 11July 25
Fall sowin 6 days
Rutabaga
July 25August 8
Fall sowin 20 days
Broccoli
August 8August 22
Fall sowin 20 days
Cabbage
August 8August 22
Fall sowin 20 days
Carrot
August 8August 22
Fall sowin 20 days
Cauliflower
August 8August 22
Fall sowin 20 days
Napa Cabbage
August 8September 5

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

Nearby weather stations

3 within 15 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.

DALECARLIA RSVR
Primary
5 km · 46 m elevation
SPRING
Apr 9
FALL
Oct 31
ROCKVILLE 1 NE
13 km · 134 m elevation
SPRING
Apr 1
FALL
Nov 6
NATL ARBORETUM DC
15 km · 15 m elevation
SPRING
Mar 29
FALL
Nov 8

Bethesda planting FAQ

When is the last spring frost in Bethesda, MD?

Bethesda's average last spring frost falls near April 9 — 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 Bethesda, MD?

Expect Bethesda's first fall frost near October 31 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Bethesda in?

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

How long is the growing season in Bethesda?

There are roughly 205 frost-free days in Bethesda (a moderate growing season), running from the average last frost around April 9 to the first fall frost near October 31.

When should I plant tomatoes in Bethesda?

In Bethesda, start tomato seeds indoors around February 12–February 26, then transplant seedlings outdoors around April 16 once the danger of frost has passed.

Planting reminders

Never miss a window in Bethesda

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

Nearby cities

8 within reach

Frost dates recorded at DALECARLIA RSVR, 5 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 Bethesda, MD — Frost Dates & Zone 7b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00182325. Retrieved from https://blissgarden.com/maryland/bethesda.
When to Plant in Bethesda, MD — Frost Dates & Zone 7b — BlissGarden