When to plant in Arnold, MD
USDA Zone 8aHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Arnold, Maryland — all computed from Arnold's nearest NOAA weather station.
In zone 8a, Arnold supports a wide range of perennials year-round; the frost dates above are what set your annual vegetable timing.
Frost probability
ANNAPOLIS POLICE BRKS · 1991–2020The 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 Arnold’s own odds, recorded at ANNAPOLIS POLICE BRKS.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Apr 24 | Apr 7 | Mar 24 | Oct 21 | Nov 2 | Nov 15 |
| 32°F | Apr 9 | Mar 27 | Mar 9 | Nov 1 | Nov 13 | Dec 1 |
| 28°F | Mar 29 | Mar 14 | Feb 26 | Nov 9 | Nov 28 | Dec 19 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Arnold, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 16 km · complete 32°F normalsWhen 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.
Arnold planting FAQ
When is the last spring frost in Arnold, MD?
On average, the last spring frost in Arnold is around March 27 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in Arnold, MD?
In Arnold, the first 32°F freeze of fall lands around November 13 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Arnold in?
Arnold is in USDA hardiness zone 8a. In zone 8a, winters are mild — many tender perennials overwinter here.
How long is the growing season in Arnold?
Arnold has about 231 frost-free days — a long growing season — between the average last spring frost (March 27) and first fall frost (November 13).
When should I plant tomatoes in Arnold?
For Arnold, sow tomatoes indoors about January 30–February 13 and move the seedlings out around April 3, after the last spring frost.
Never miss a window in Arnold
An email when it’s time to start seeds, transplant, and sow — timed to Arnold’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Lake Shore · 6 km
- Severna Park · 7 km
- Parole · 7 km
- Annapolis · 8 km
- Annapolis Neck · 12 km
- Pasadena · 13 km
- Riviera Beach · 14 km
- Glen Burnie · 15 km
Frost dates recorded at ANNAPOLIS POLICE BRKS, 6 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Arnold, MD — Frost Dates & Zone 8a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00180193. Retrieved from https://blissgarden.com/maryland/arnold.