Last frost dates in Maryland
43 NOAA weather stations in Maryland have thirty years of frost records. The median station sees its last 32 °F night around Apr 8; across the state that ranges from Mar 22 to May 9, so pick the station nearest you rather than a state-wide figure.
| Plan sowing from this date | ||||||
|---|---|---|---|---|---|---|
| SOLOMONS | Mar 22 | Apr 5 | Mar 6 | Nov 26 | 248 | Plan sowing from this date → |
| ANNAPOLIS NAF | Mar 23 | Apr 6 | Mar 8 | Nov 20 | 241 | Plan sowing from this date → |
| MD SCI CTR BALTIMORE | Mar 24 | Apr 4 | Mar 8 | Nov 21 | 244 | Plan sowing from this date → |
| ANNAPOLIS POLICE BRKS | Mar 27 | Apr 9 | Mar 9 | Nov 13 | 234 | Plan sowing from this date → |
| NATL ARBORETUM DC | Mar 29 | Apr 11 | Mar 15 | Nov 8 | 224 | Plan sowing from this date → |
| PATUXENT RIVER NAS | Mar 29 | Apr 10 | Mar 15 | Nov 15 | 230 | Plan sowing from this date → |
| STEVENSVILLE 2SW | Mar 29 | Apr 8 | Mar 15 | Nov 12 | 228 | Plan sowing from this date → |
| ST INIGOES WEBSTER NOLF | Mar 30 | Apr 11 | Mar 14 | Nov 14 | 229 | Plan sowing from this date → |
| ASSATEAGUE | Mar 31 | Apr 13 | Mar 15 | Nov 15 | 228 | Plan sowing from this date → |
| ROCKVILLE 1 NE | Apr 1 | Apr 15 | Mar 19 | Nov 6 | 219 | Plan sowing from this date → |
| ROYAL OAK 2 SSW | Apr 1 | Apr 15 | Mar 18 | Nov 7 | 220 | Plan sowing from this date → |
| CYLBURN | Apr 2 | Apr 13 | Mar 20 | Nov 7 | 220 | Plan sowing from this date → |
| FREDERICK POLICE BRKS | Apr 2 | Apr 15 | Mar 17 | Nov 6 | 218 | Plan sowing from this date → |
| SALISBURY 2N | Apr 2 | Apr 16 | Mar 16 | Nov 10 | 222 | Plan sowing from this date → |
| CHESTERTOWN | Apr 3 | Apr 16 | Mar 20 | Nov 5 | 217 | Plan sowing from this date → |
| CONOWINGO DAM | Apr 3 | Apr 18 | Mar 22 | Nov 6 | 217 | Plan sowing from this date → |
| OXON HILL | Apr 3 | Apr 15 | Mar 19 | Nov 8 | 217 | Plan sowing from this date → |
| SALISBURY | Apr 3 | Apr 25 | Mar 18 | Nov 7 | 217 | Plan sowing from this date → |
| LAUREL 3 W | Apr 5 | Apr 19 | Mar 21 | Nov 9 | 218 | Plan sowing from this date → |
| HAGERSTOWN WASHINGTON CO AP | Apr 7 | Apr 21 | Mar 25 | Nov 4 | 209 | Plan sowing from this date → |
| OCEAN CITY MUNI AP | Apr 7 | Apr 23 | Mar 24 | Nov 2 | 209 | Plan sowing from this date → |
| VIENNA | Apr 8 | Apr 23 | Mar 24 | Nov 4 | 209 | Plan sowing from this date → |
| DALECARLIA RSVR | Apr 9 | Apr 26 | Mar 27 | Oct 31 | 202 | Plan sowing from this date → |
| UPPER MARLBORO 3 NNW | Apr 9 | Apr 24 | Mar 27 | Oct 29 | 203 | Plan sowing from this date → |
| ABERDEEN PHILLIPS FLD | Apr 10 | Apr 30 | Mar 27 | Oct 30 | 201 | Plan sowing from this date → |
| BALTIMORE WASH INTL AP | Apr 10 | Apr 25 | Mar 27 | Oct 31 | 204 | Plan sowing from this date → |
| BELTSVILLE | Apr 10 | May 1 | Mar 27 | Nov 1 | 202 | Plan sowing from this date → |
| SALISBURY WICOMICO RGNL AP | Apr 10 | Apr 30 | Mar 28 | Oct 30 | 201 | Plan sowing from this date → |
| SNOW HILL 4 N | Apr 10 | Apr 28 | Mar 27 | Oct 31 | 202 | Plan sowing from this date → |
| HAGERSTOWN 1 E | Apr 11 | Apr 27 | Mar 29 | Oct 28 | 199 | Plan sowing from this date → |
| CATOCTIN MTN PARK | Apr 14 | Apr 30 | Apr 2 | Oct 30 | 197 | Plan sowing from this date → |
| DAMASCUS 3 SSW | Apr 14 | May 2 | Mar 31 | Oct 29 | 196 | Plan sowing from this date → |
| CUMBERLAND 2 | Apr 15 | May 5 | Apr 2 | Oct 24 | 190 | Plan sowing from this date → |
| MECHANICSVILLE 5 NE | Apr 17 | May 2 | Mar 31 | Oct 27 | 195 | Plan sowing from this date → |
| MILLERS 4 NE | Apr 19 | May 8 | Apr 4 | Oct 25 | 188 | Plan sowing from this date → |
| EMMITSBURG 2 SE | Apr 22 | May 9 | Apr 7 | Oct 20 | 179 | Plan sowing from this date → |
| GLENN DALE BELL STN | Apr 22 | May 9 | Apr 3 | Oct 22 | 183 | Plan sowing from this date → |
| SMITHSBURG 2NW | Apr 25 | May 11 | Apr 12 | Oct 19 | 176 | Plan sowing from this date → |
| SHARPSBURG 5 S | Apr 26 | May 15 | Apr 11 | Oct 18 | 175 | Plan sowing from this date → |
| FROSTBURG 2 | Apr 29 | May 15 | Apr 14 | Oct 18 | 171 | Plan sowing from this date → |
| SAVAGE RVR DAM | Apr 29 | May 15 | Apr 11 | Oct 20 | 174 | Plan sowing from this date → |
| OAKLAND 1 SE | May 6 | May 23 | Apr 21 | Oct 9 | 156 | Plan sowing from this date → |
| SINES DEEP CREEK | May 9 | May 30 | Apr 21 | Oct 11 | 155 | Plan sowing from this date → |
How to read the three dates
Average is the date by which, in half of the years between 1991 and 2020, the last 32 °F night had already happened. Safe is later: only one year in ten saw a frost after it, which is the date to transplant tomatoes and peppers, both killed by a single frost. Early is the risky end, with a frost after it in nine years out of ten.
Every figure is for the weather station, not for your garden. A valley bottom, a north slope or a spot near a lake can run a week or two either way. Cities are warmer than the countryside around them.
Where the numbers come from
The dates are NOAA's U.S. Climate Normals for 1991 to 2020, computed by the National Centers for Environmental Information for every station with thirty years of daily minimum temperatures. ZIP codes are matched to the nearest such station within 150 km using U.S. Census Bureau ZIP Code Tabulation Area centroids. Stations that never see a frost, such as much of south Florida, report no date and are left out.