Frost Dates & Planting Calendar for Beulah, ND

The average first fall frost in Beulah, ND is September 20, and the average last spring frost is May 21, giving a growing season of about 121 days.

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

Last Spring Frost

May 21

Safe Jun 3 Typical May 21 Risky May 7

First Fall Frost

September 20

Safe Sep 5 Typical Sep 20 Risky Oct 4

Growing Season

121 days

Typical last frost to typical first frost.

USDA Hardiness Zone

Zone 4a

Very cold winters, focus on short-season varieties and cold-hardy perennials.

Data: NOAA station BEULAH 1 W, ND US, 1 km away.

— days until the typical last spring frost

How Beulah Compares

Beulah's typical last spring frost (May 21) comes later than in 90% of the 20 North Dakota cities we track.
Its 121-day growing season is 21 days shorter than the North Dakota median of 142 days.
Compared with Mandan (83 km away), Beulah's last spring frost comes 8 days later than Mandan's, and its first fall frost arrives 7 days earlier.
August is the warmest month (average high 86°F) and January the coldest (average low 3°F).

Monthly Temperatures

Avg. high Avg. temp Avg. low

Planting Calendar

Vegetables
Crop	Start indoors	Direct sow	Transplant	Fall planting	Maturity	Notes
Tomato	Mar 26 – Apr 9	—	May 28 – Jun 4	—	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 12 – Mar 26	—	May 28 – Jun 11	—	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 12 – Mar 26	—	Jun 4 – Jun 11	—	65–85 days	Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant.
Cucumber	Apr 23 – Apr 30	May 28 – Jun 4	May 28 – Jun 4	—	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 30 – May 7	May 28 – Jun 11	May 28 – Jun 4	—	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 23 – Apr 30	May 28 – Jun 11	May 28 – Jun 4	—	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 28 – Jun 11	—	—	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 23 – Apr 30	—	Jun 4 – Jun 11	—	70–90 days	Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost.
Cantaloupe	Apr 23 – Apr 30	—	Jun 4 – Jun 11	—	70–90 days	Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting.
Corn	—	May 21 – Jun 4	—	—	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 21 – Jun 4	—	—	50–65 days	Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush.
Pea	—	Apr 9 – Apr 23	—	—	55–70 days	Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.
Lettuce	—	Apr 23 – May 7	—	Jul 26 – Aug 9	45–60 days	Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts.
Spinach	—	Apr 9 – Apr 23	—	Jul 26 – Aug 9	40–50 days	Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.
Kale	—	Apr 23 – May 7	—	Jul 12 – Jul 26	50–65 days	Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants.
Arugula	—	Apr 23 – May 7	—	Aug 9 – Aug 16	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 30 – May 14	—	—	50–60 days	Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too.
Broccoli	Apr 2 – Apr 16	—	Apr 30 – May 7	Jul 19 – Jul 26	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	Apr 2 – Apr 16	—	May 7 – May 14	Jul 12 – Jul 19	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	Apr 2 – Apr 16	—	Apr 23 – May 7	Jul 12 – Jul 26	60–100 days	Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost.
Brussels Sprouts	Apr 2 – Apr 16	—	Apr 30 – May 14	—	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 23 – May 7	—	Jun 28 – Jul 12	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 23 – May 7	—	Jul 12 – Jul 26	50–65 days	Direct sow 2-4 weeks before last frost; tolerates light frost.
Radish	—	Apr 16 – Apr 30	—	Aug 9 – Aug 23	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 23 – May 7	—	Jul 12 – Jul 26	40–60 days	Cold-hardy; direct sow 2-4 weeks before last frost.
Onion	Mar 12 – Mar 26	—	Apr 23 – May 7	—	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	—	—	—	Aug 23 – Sep 6	240–270 days	Fall-planted crop only; not planted in spring in most climates.
Potato	—	Apr 23 – May 7	—	—	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	—	—	Jun 4 – Jun 18	—	90–120 days	Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive.
Asparagus	—	—	Apr 23 – May 7	—	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
Crop	Start indoors	Direct sow	Transplant	Fall planting	Maturity	Notes
Basil	Apr 9 – Apr 16	—	May 28 – Jun 4	—	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 30 – May 14	—	Jul 26 – Aug 9	45–70 days	Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring.
Parsley	Mar 26 – Apr 9	—	May 7 – May 14	—	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 30 – May 14	—	—	40–60 days	Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer.
Oregano	Mar 26 – Apr 9	—	May 21 – May 28	—	80–90 days	Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date.
Thyme	Mar 26 – Apr 9	—	May 21 – May 28	—	85–95 days	Perennial herb, slow from seed; start indoors 6-8 weeks before last frost, transplant around/after last frost.

Flowers
Crop	Start indoors	Direct sow	Transplant	Fall planting	Maturity	Notes
Sunflower	—	May 28 – Jun 11	—	—	70–100 days	Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting.
Zinnia	Apr 23 – Apr 30	May 28 – Jun 11	May 28 – Jun 4	—	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 9 – Apr 23	—	May 28 – Jun 4	—	45–60 days	Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed.
Cosmos	Apr 23 – Apr 30	May 28 – Jun 11	May 28 – Jun 4	—	60–90 days	Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early.
Nasturtium	—	May 28 – Jun 11	—	—	50–65 days	Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed.
Dahlia	—	—	May 28 – Jun 11	—	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 Beulah, ND?

Based on 1991–2020 NOAA climate normals for the BEULAH 1 W, ND US station, the last spring frost in Beulah typically falls around May 21. A cautious gardener might wait until June 3 (only a 10% chance of a later frost), while May 7 marks an earlier, higher-risk planting date.

When is the first frost in Beulah, ND in fall?

The first fall frost in Beulah typically arrives around September 20. To stay safe, assume frost could start as early as September 5; in milder years it can hold off until October 4.

How long is the growing season in Beulah, ND?

Beulah's average frost-free growing season is about 121 days, running from the typical last spring frost (May 21) to the typical first fall frost (September 20).

What USDA hardiness zone is Beulah, ND in?

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