Frost Dates & Planting Calendar for St Johnsbury, VT

Plan your garden around St Johnsbury, VT's typical frost-free growing season, using NOAA climate normals and a 42-crop planting calendar built for this location.

Last Spring Frost
May 13
Safe May 25 Typical May 13 Risky Apr 30
First Fall Frost
October 3
Safe Sep 21 Typical Oct 3 Risky Oct 16
Growing Season
143 days
Typical last frost to typical first frost.
USDA Hardiness Zone
Zone 4b
Very cold winters, focus on short-season varieties and cold-hardy perennials.
Data: NOAA station SAINT JOHNSBURY, VT US, 0.7 km away.
days until the typical last spring frost

Monthly Temperatures

Monthly normal temperatures (°F) 20°40°60°80° JFMAMJJASOND
Avg. high Avg. temp Avg. low

Planting Calendar

Vegetables
CropStart indoorsDirect sowTransplantFall plantingMaturityNotes
Tomato Mar 18 – Apr 1 May 20 – May 27 60–85 days Start indoors 6-8 weeks before last frost; transplant out 1-2 weeks after last frost once soil has warmed.
Pepper Mar 4 – Mar 18 May 20 – Jun 3 60–90 days Slow to germinate; start indoors 8-10 weeks before last frost. Transplant only once nights stay above 55F, 1-3 weeks after last frost.
Eggplant Mar 4 – Mar 18 May 27 – Jun 3 65–85 days Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant.
Cucumber Apr 15 – Apr 22 May 20 – May 27 May 20 – May 27 50–65 days Can be started indoors 3-4 weeks before transplanting, or direct-sown 1-2 weeks after last frost once soil is warm.
Zucchini Apr 22 – Apr 29 May 20 – Jun 3 May 20 – May 27 45–55 days Fast-growing squash; direct sow 1-3 weeks after last frost, or start indoors 2-3 weeks early for a head start.
Winter Squash Apr 15 – Apr 22 May 20 – Jun 3 May 20 – May 27 80–110 days Long season; direct sow after soil warms, or start indoors 3-4 weeks before last frost in short-season climates.
Pumpkin May 20 – Jun 3 90–120 days Direct sow 1-3 weeks after last frost; back-time from your first fall frost so the 90-120 day maturity window lands before it.
Watermelon Apr 15 – Apr 22 May 27 – Jun 3 70–90 days Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost.
Cantaloupe Apr 15 – Apr 22 May 27 – Jun 3 70–90 days Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting.
Corn May 13 – May 27 60–100 days Direct sow at last frost to 2 weeks after, once soil reaches 60F; does not transplant well. Succession sow every 2 weeks.
Green Bean May 13 – May 27 50–65 days Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush.
Pea Apr 1 – Apr 15 55–70 days Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.
Lettuce Apr 15 – Apr 29 Aug 8 – Aug 22 45–60 days Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts.
Spinach Apr 1 – Apr 15 Aug 8 – Aug 22 40–50 days Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.
Kale Apr 15 – Apr 29 Jul 25 – Aug 8 50–65 days Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants.
Arugula Apr 15 – Apr 29 Aug 22 – Aug 29 30–40 days Fast-growing, cold-tolerant green; direct sow 2-4 weeks before last frost, succession sow every 2-3 weeks.
Swiss Chard Apr 22 – May 6 50–60 days Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too.
Broccoli Mar 25 – Apr 8 Apr 22 – Apr 29 Aug 1 – Aug 8 55–80 days Start indoors 5-7 weeks before last frost; transplant out 2-3 weeks before last frost (hardens off to light frost).
Cauliflower Mar 25 – Apr 8 Apr 29 – May 6 Jul 25 – Aug 1 55–85 days Fussier than broccoli about temperature swings; start indoors 5-7 weeks before last frost, transplant 1-2 weeks before last frost.
Cabbage Mar 25 – Apr 8 Apr 15 – Apr 29 Jul 25 – Aug 8 60–100 days Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost.
Brussels Sprouts Mar 25 – Apr 8 Apr 22 – May 6 90–110 days Long-season crop best timed to mature after a light fall frost for sweetest flavor; start indoors 5-7 weeks before last frost.
Carrot Apr 15 – Apr 29 Jul 11 – Jul 25 60–80 days Direct sow only (does not transplant); sow 2-4 weeks before last frost, as soon as soil can be worked.
Beet Apr 15 – Apr 29 Jul 25 – Aug 8 50–65 days Direct sow 2-4 weeks before last frost; tolerates light frost.
Radish Apr 8 – Apr 22 Aug 22 – Sep 5 22–30 days Very fast and cold-hardy; direct sow 3-5 weeks before last frost, as soon as soil can be worked.
Turnip Apr 15 – Apr 29 Jul 25 – Aug 8 40–60 days Cold-hardy; direct sow 2-4 weeks before last frost.
Onion Mar 4 – Mar 18 Apr 15 – Apr 29 90–120 days Start seeds indoors 8-10 weeks before last frost (or use sets/transplants); set out 2-4 weeks before last frost, very cold-tolerant as seedlings.
Garlic Sep 5 – Sep 19 240–270 days Fall-planted crop only; not planted in spring in most climates.
Potato Apr 15 – Apr 29 70–120 days Plant seed potatoes 2-4 weeks before last frost, as soon as soil can be worked and is above 45F; light frost on emerging foliage is usually tolerated.
Sweet Potato May 27 – Jun 10 90–120 days Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive.
Asparagus Apr 15 – Apr 29 730–1095 days Perennial; plant crowns 2-4 weeks before last frost as soon as soil can be worked. Takes 2-3 years to full production.
Herbs
CropStart indoorsDirect sowTransplantFall plantingMaturityNotes
Basil Apr 1 – Apr 8 May 20 – May 27 50–70 days Very frost/cold sensitive; start indoors 5-6 weeks before last frost, transplant only after all danger of frost (1-2 weeks after) and nights stay warm.
Cilantro Apr 22 – May 6 Aug 8 – Aug 22 45–70 days Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring.
Parsley Mar 18 – Apr 1 Apr 29 – May 6 70–90 days Slow to germinate; start indoors 6-8 weeks before last frost, transplant 1-2 weeks before last frost (biennial, cold-tolerant).
Dill Apr 22 – May 6 40–60 days Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer.
Oregano Mar 18 – Apr 1 May 13 – May 20 80–90 days Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date.
Thyme Mar 18 – Apr 1 May 13 – May 20 85–95 days Perennial herb, slow from seed; start indoors 6-8 weeks before last frost, transplant around/after last frost.
Flowers
CropStart indoorsDirect sowTransplantFall plantingMaturityNotes
Sunflower May 20 – Jun 3 70–100 days Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting.
Zinnia Apr 15 – Apr 22 May 20 – Jun 3 May 20 – May 27 60–70 days Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms.
Marigold Apr 1 – Apr 15 May 20 – May 27 45–60 days Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed.
Cosmos Apr 15 – Apr 22 May 20 – Jun 3 May 20 – May 27 60–90 days Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early.
Nasturtium May 20 – Jun 3 50–65 days Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed.
Dahlia May 20 – Jun 3 90–120 days Plant tubers 1-3 weeks after last frost once soil is warm (60F+); very frost-sensitive.

Date ranges are estimates based on university extension guidelines and this city's NOAA frost normals — not a guarantee. Scroll to see all columns on narrow screens.

Frequently Asked Questions

When is the last frost in St Johnsbury, VT?

Based on 1991–2020 NOAA climate normals for the SAINT JOHNSBURY, VT US station, the last spring frost in St Johnsbury typically falls around May 13. A cautious gardener might wait until May 25 (only a 10% chance of a later frost), while April 30 marks an earlier, higher-risk planting date.

When is the first frost in St Johnsbury, VT in fall?

The first fall frost in St Johnsbury typically arrives around October 3. To stay safe, assume frost could start as early as September 21; in milder years it can hold off until October 16.

How long is the growing season in St Johnsbury, VT?

St Johnsbury's average frost-free growing season is about 143 days, running from the typical last spring frost (May 13) to the typical first fall frost (October 3).

What USDA hardiness zone is St Johnsbury, VT in?

St Johnsbury, VT is in USDA plant hardiness zone 4b, per the USDA's 2023 Plant Hardiness Zone Map. Very cold winters, focus on short-season varieties and cold-hardy perennials.

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