FrostDateByZip

Frost dates for 03838Glen, NH

The average last spring frost in Glen is May 7 and the average first fall frost is October 5, giving a typical growing season of about 150 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
May 7

Safer after May 19 (1-in-10 risk)

Average first fall frost
Oct 5

Possible by Sep 23 (1-in-10 risk)

Growing season
150 days

Last frost typically in 187 days

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
TemperatureLast spring: 90% / 50% / 10% chanceFirst fall: 10% / 50% / 90% chanceGrowing season (50%)Years with at least one
Light frost (36°F)May 6 · May 18 · May 31Sep 13 · Sep 26 · Oct 7130 days100%
Frost / freeze (32°F)Apr 27 · May 7 · May 19Sep 23 · Oct 5 · Oct 20150 days100%
Hard freeze (28°F)Apr 13 · Apr 26 · May 9Oct 1 · Oct 17 · Nov 4174 days100%

Planting calendar for Glen

Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.

CropTaskWindow
TomatoesStart seeds indoorsApr 6 – Jun 12
TomatoesTransplant outdoorsMay 23 – Jun 15
PeppersStart seeds indoorsApr 6 – May 7
PeppersTransplant outdoorsJun 6 – Jul 7
EggplantStart seeds indoorsApr 23 – May 22
EggplantTransplant outdoorsJun 6 – Jul 7
CucumbersSow outdoorsJun 6 – Jun 25
Summer squashSow outdoorsMay 23 – Jul 7
Winter squash & pumpkinsSow outdoorsJun 6 – Jul 7
Snap beansSow outdoorsMay 23 – Jul 18
Sweet cornSow outdoorsMay 23 – Jun 15
Watermelon & cantaloupeSow outdoorsJun 6 – Jul 7
OkraSow outdoorsMay 30 – Jun 22
PeasSow outdoors (spring)Apr 6 – May 22
PotatoesPlant outdoors (spring)Apr 6 – Jun 6
OnionsStart seeds indoors (spring)Feb 23 – Mar 22
OnionsTransplant outdoors (spring)Apr 23 – May 22
BroccoliStart seeds indoors (spring)Mar 19 – Apr 22
BroccoliTransplant outdoors (spring)Apr 23 – May 22
BroccoliStart seeds indoors (fall)Jun 5 – Jun 15
BroccoliTransplant outdoors (fall)Jul 5 – Jul 16
CabbageStart seeds indoors (spring)Mar 9 – Apr 6
CabbageTransplant outdoors (spring)Apr 6 – May 7
CabbageStart seeds indoors (fall)May 26 – Jun 25
CabbageTransplant outdoors (fall)Jun 25 – Jul 26
Leaf lettuceSow outdoors (spring)Apr 6 – Jun 22
Leaf lettuceSow outdoors (fall)Jun 25 – Aug 11
SpinachSow outdoors (spring)Mar 30 – May 13
SpinachSow outdoors (fall)Jul 12 – Aug 16
RadishesSow outdoors (spring)Apr 6 – May 27
RadishesSow outdoors (fall)Jun 25 – Aug 26
KaleSow outdoors (spring)Apr 23 – May 13
KaleSow outdoors (fall)Jun 18 – Jul 26
CarrotsSow outdoors (spring)May 7 – Jun 22
CarrotsSow outdoors (fall)May 26 – Jul 11
GarlicPlant outdoors (fall)Sep 25 – Oct 26

Where these dates come from

ZIP code 03838 is matched to the NOAA station N Conway, NH, 7.1 km away, at 522 ft elevation (19 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
N Conway, NH (used)522 ftMay 7Oct 5
Pinkham Notch, NH2,025 ftMay 18Oct 1
Mt Washington, NH6,267 ft——
Fryeburg E Slopes Ap, ME445 ftMay 17Sep 25

Frost dates near Glen

Frequently asked questions

When is the last frost in Glen, NH?
For ZIP code 03838, the average last spring frost (32°F) is May 7, based on NOAA 1991-2020 climate normals for the N Conway, NH weather station. There is a 1-in-10 chance of a frost after May 19.
When is the first frost in Glen, NH?
The average first fall frost (32°F) is October 5. There is a 1-in-10 chance of frost by September 23, so tender plants are at risk from that point on.
How long is the growing season in 03838?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 150 days long.
Are these frost dates a forecast?
No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.