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When to plant in Rosaryville, MD

USDA Zone 7b

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

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

Station · UPPER MARLBORO 3 NNW · 10.7 km
Last spring frost
April 9
50% chance · 32°F
First fall frost
October 29
50% chance · 32°F
Growing season
203 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for RosaryvilleA year-band showing 32°F frost risk from January to December for Rosaryville: last spring frost around April 9, first fall frost around October 29, about 203 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

UPPER MARLBORO 3 NNW · 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 Rosaryville’s own odds, recorded at UPPER MARLBORO 3 NNW.

Frost-probability curves for RosaryvilleProbability 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 29, giving about 203 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 12Apr 24Apr 8Oct 5Oct 19Nov 1
32°FApr 24Apr 9Mar 27Oct 14Oct 29Nov 11
28°FApr 12Mar 30Mar 14Oct 27Nov 10Nov 25

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 9July 23
Fall sowin 4 days
Rutabaga
July 23August 6
Fall sowin 18 days
Broccoli
August 6August 20
Fall sowin 18 days
Cabbage
August 6August 20
Fall sowin 18 days
Carrot
August 6August 20
Fall sowin 18 days
Cauliflower
August 6August 20
Fall sowin 18 days
Napa Cabbage
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 Rosaryville, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 20 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.

UPPER MARLBORO 3 NNW
Primary
11 km · 40 m elevation
SPRING
Apr 9
FALL
Oct 29
OXON HILL
15 km · 58 m elevation
SPRING
Apr 3
FALL
Nov 8
WASHINGTON REAGAN AP
20 km · 3 m elevation
SPRING
Mar 24
FALL
Nov 18

Rosaryville planting FAQ

When is the last spring frost in Rosaryville, MD?

Rosaryville'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 Rosaryville, MD?

Expect Rosaryville's first fall frost near October 29 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Rosaryville in?

Rosaryville 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 Rosaryville?

There are roughly 203 frost-free days in Rosaryville (a moderate growing season), running from the average last frost around April 9 to the first fall frost near October 29.

When should I plant tomatoes in Rosaryville?

In Rosaryville, 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 Rosaryville

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

Nearby cities

8 within reach

Frost dates recorded at UPPER MARLBORO 3 NNW, 11 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 Rosaryville, MD — Frost Dates & Zone 7b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00189070. Retrieved from https://blissgarden.com/maryland/rosaryville.
When to Plant in Rosaryville, MD — Frost Dates & Zone 7b — BlissGarden