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USDA hardiness zone lookup

Manchester, NH — USDA Zone 5b

Manchester, New Hampshire · 144-day growing season

Frost dates and growing season in Manchester

USDA hardiness zoneZone 5b
Average last spring frostMay 10
Average first fall frostOctober 1
Growing season length~144 days
Temperature range (F)-20 to -10°F
Temperature range (C)-29 to -23°C

All of Manchester's mapped ZIP codes fall in the same hardiness band, Zone 5b.

These are 50%-probability averages modeled from Manchester's USDA hardiness zone and regional climate normals — not a single-station reading. In a typical year the last spring frost will have passed by May 10, but a colder-than-average year can run 1-2 weeks later. Plant tender crops (tomatoes, peppers, basil) once both soil and night temperatures are consistently warm — a thermometer beats the calendar.

Growing season in Manchester

Manchester, New Hampshire sits in USDA Zone 5b, with roughly 144 frost-free days between an average last spring frost around May 10 and a first fall frost around October 1. That is a standard temperate season — most common vegetables finish comfortably, and a single main planting plus one succession round works well.

What grows in Manchester

Manchester falls in USDA Zone 5b, so the same hardiness constraints apply as the full Zone 5 guide. Vegetables, herbs, and fruit trees rated to Zone 5b (or hardier) will overwinter here in a typical year.

What to plant in Manchester this week

Manchester's last frost is around May 10. This is the spring transplant window — start tomatoes and peppers indoors if you haven't, and direct-sow cold-tolerant crops now.

Full planting calendar for Manchester

Crop-by-crop sowing, transplant, and harvest dates calibrated to zone 5 averages:

ZIP codes in Manchester

Drill down to the precise frost window and planting calendar for a specific ZIP in Manchester:

Local microclimate notes

Zone tables give you the average — but Manchestergardens vary. South-facing walls and paved areas can run a full half-zone warmer than the published rating. Low-lying spots, frost pockets, and shaded north sides can run colder. If you've gardened here a few seasons, your own frost record — the last time you actually got frost damage — beats any national average.

Source and methodology

Hardiness zone from the USDA Plant Hardiness Zone Map (2023 revision). Frost-date and growing-season figures are modeled from Manchester's USDA hardiness zone and regional NOAA 1991-2020 climate normals — zone-level estimates, not a per-station record, so treat them as planning guidance and confirm against your own local frost history. Crop recommendations draw on US Cooperative Extension references, curated by the Growli editorial team. Last reviewed June 2026.

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