Frost Dates & Planting Calendar for Ham Lake, MN

The average first fall frost in Ham Lake, MN is October 2, and the average last spring frost is May 5, giving a growing season of about 148 days.

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

Last Spring Frost

May 5

Safe May 21 Typical May 5 Risky Apr 23

First Fall Frost

October 2

Safe Sep 18 Typical Oct 2 Risky Oct 16

Growing Season

148 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 ANDOVER 1N, MN US, 3.4 km away.

— days until the typical last spring frost

How Ham Lake Compares

Ham Lake's typical last spring frost (May 5) comes later than in 78% of the 104 Minnesota cities we track.
Its 148-day growing season is 13 days shorter than the Minnesota median of 161 days.
Ham Lake shares its NOAA weather station with Andover (4 km away), so their typical frost dates are the same.
July is the warmest month (average high 82°F) and January the coldest (average low 2°F).

Monthly Temperatures

Avg. high Avg. temp Avg. low

Planting Calendar

Vegetables
Crop	Start indoors	Direct sow	Transplant	Fall planting	Maturity	Notes
Tomato	Mar 10 – Mar 24	—	May 12 – May 19	—	60–85 days	Start indoors 6-8 weeks before last frost; transplant out 1-2 weeks after last frost once soil has warmed.
Pepper	Feb 24 – Mar 10	—	May 12 – May 26	—	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	Feb 24 – Mar 10	—	May 19 – May 26	—	65–85 days	Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant.
Cucumber	Apr 7 – Apr 14	May 12 – May 19	May 12 – May 19	—	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 14 – Apr 21	May 12 – May 26	May 12 – May 19	—	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 7 – Apr 14	May 12 – May 26	May 12 – May 19	—	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 12 – May 26	—	—	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 7 – Apr 14	—	May 19 – May 26	—	70–90 days	Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost.
Cantaloupe	Apr 7 – Apr 14	—	May 19 – May 26	—	70–90 days	Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting.
Corn	—	May 5 – May 19	—	—	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 5 – May 19	—	—	50–65 days	Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush.
Pea	—	Mar 24 – Apr 7	—	—	55–70 days	Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.
Lettuce	—	Apr 7 – Apr 21	—	Aug 7 – Aug 21	45–60 days	Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts.
Spinach	—	Mar 24 – Apr 7	—	Aug 7 – Aug 21	40–50 days	Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.
Kale	—	Apr 7 – Apr 21	—	Jul 24 – Aug 7	50–65 days	Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants.
Arugula	—	Apr 7 – Apr 21	—	Aug 21 – Aug 28	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 14 – Apr 28	—	—	50–60 days	Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too.
Broccoli	Mar 17 – Mar 31	—	Apr 14 – Apr 21	Jul 31 – Aug 7	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 17 – Mar 31	—	Apr 21 – Apr 28	Jul 24 – Jul 31	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 17 – Mar 31	—	Apr 7 – Apr 21	Jul 24 – Aug 7	60–100 days	Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost.
Brussels Sprouts	Mar 17 – Mar 31	—	Apr 14 – Apr 28	—	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 7 – Apr 21	—	Jul 10 – Jul 24	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 7 – Apr 21	—	Jul 24 – Aug 7	50–65 days	Direct sow 2-4 weeks before last frost; tolerates light frost.
Radish	—	Mar 31 – Apr 14	—	Aug 21 – Sep 4	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 7 – Apr 21	—	Jul 24 – Aug 7	40–60 days	Cold-hardy; direct sow 2-4 weeks before last frost.
Onion	Feb 24 – Mar 10	—	Apr 7 – Apr 21	—	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 4 – Sep 18	240–270 days	Fall-planted crop only; not planted in spring in most climates.
Potato	—	Apr 7 – Apr 21	—	—	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 19 – Jun 2	—	90–120 days	Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive.
Asparagus	—	—	Apr 7 – Apr 21	—	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	Mar 24 – Mar 31	—	May 12 – May 19	—	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 14 – Apr 28	—	Aug 7 – Aug 21	45–70 days	Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring.
Parsley	Mar 10 – Mar 24	—	Apr 21 – Apr 28	—	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 14 – Apr 28	—	—	40–60 days	Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer.
Oregano	Mar 10 – Mar 24	—	May 5 – May 12	—	80–90 days	Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date.
Thyme	Mar 10 – Mar 24	—	May 5 – May 12	—	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 12 – May 26	—	—	70–100 days	Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting.
Zinnia	Apr 7 – Apr 14	May 12 – May 26	May 12 – May 19	—	60–70 days	Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms.
Marigold	Mar 24 – Apr 7	—	May 12 – May 19	—	45–60 days	Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed.
Cosmos	Apr 7 – Apr 14	May 12 – May 26	May 12 – May 19	—	60–90 days	Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early.
Nasturtium	—	May 12 – May 26	—	—	50–65 days	Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed.
Dahlia	—	—	May 12 – May 26	—	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 Ham Lake, MN?

Based on 1991–2020 NOAA climate normals for the ANDOVER 1N, MN US station, the last spring frost in Ham Lake typically falls around May 5. A cautious gardener might wait until May 21 (only a 10% chance of a later frost), while April 23 marks an earlier, higher-risk planting date.

When is the first frost in Ham Lake, MN in fall?

The first fall frost in Ham Lake typically arrives around October 2. To stay safe, assume frost could start as early as September 18; in milder years it can hold off until October 16.

How long is the growing season in Ham Lake, MN?

Ham Lake's average frost-free growing season is about 148 days, running from the typical last spring frost (May 5) to the typical first fall frost (October 2).

What USDA hardiness zone is Ham Lake, MN in?

Ham Lake, MN 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.