Frost Dates & Planting Calendar for Troy, MI
Plan your garden around Troy, MI's typical frost-free growing season, using NOAA climate normals and a 42-crop planting calendar built for this location.
Last Spring Frost
April 26
Safe May 12
Typical Apr 26
Risky Apr 15
First Fall Frost
October 22
Safe Oct 7
Typical Oct 22
Risky Nov 4
Growing Season
177 days
Typical last frost to typical first frost.
USDA Hardiness Zone
Zone 6b
A classic four-season climate with cold winters and a solid summer growing season.
Data: NOAA station PONTIAC WWTP, MI US, 9.4 km away.
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days until the typical last spring frost
Monthly Temperatures
Avg. high
Avg. temp
Avg. low
Planting Calendar
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Tomato | Mar 1 – Mar 15 | — | May 3 – May 10 | — | 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 15 – Mar 1 | — | May 3 – May 17 | — | 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 15 – Mar 1 | — | May 10 – May 17 | — | 65–85 days | Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant. |
| Cucumber | Mar 29 – Apr 5 | May 3 – May 10 | May 3 – May 10 | — | 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 5 – Apr 12 | May 3 – May 17 | May 3 – May 10 | — | 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 | Mar 29 – Apr 5 | May 3 – May 17 | May 3 – May 10 | — | 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 3 – May 17 | — | — | 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 | Mar 29 – Apr 5 | — | May 10 – May 17 | — | 70–90 days | Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost. |
| Cantaloupe | Mar 29 – Apr 5 | — | May 10 – May 17 | — | 70–90 days | Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting. |
| Corn | — | Apr 26 – May 10 | — | — | 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 | — | Apr 26 – May 10 | — | — | 50–65 days | Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush. |
| Pea | — | Mar 15 – Mar 29 | — | — | 55–70 days | Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Lettuce | — | Mar 29 – Apr 12 | — | Aug 27 – Sep 10 | 45–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts. |
| Spinach | — | Mar 15 – Mar 29 | — | Aug 27 – Sep 10 | 40–50 days | Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Kale | — | Mar 29 – Apr 12 | — | Aug 13 – Aug 27 | 50–65 days | Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants. |
| Arugula | — | Mar 29 – Apr 12 | — | Sep 10 – Sep 17 | 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 5 – Apr 19 | — | — | 50–60 days | Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too. |
| Broccoli | Mar 8 – Mar 22 | — | Apr 5 – Apr 12 | Aug 20 – Aug 27 | 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 8 – Mar 22 | — | Apr 12 – Apr 19 | Aug 13 – Aug 20 | 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 8 – Mar 22 | — | Mar 29 – Apr 12 | Aug 13 – Aug 27 | 60–100 days | Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost. |
| Brussels Sprouts | Mar 8 – Mar 22 | — | Apr 5 – Apr 19 | — | 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 | — | Mar 29 – Apr 12 | — | Jul 30 – Aug 13 | 60–80 days | Direct sow only (does not transplant); sow 2-4 weeks before last frost, as soon as soil can be worked. |
| Beet | — | Mar 29 – Apr 12 | — | Aug 13 – Aug 27 | 50–65 days | Direct sow 2-4 weeks before last frost; tolerates light frost. |
| Radish | — | Mar 22 – Apr 5 | — | Sep 10 – Sep 24 | 22–30 days | Very fast and cold-hardy; direct sow 3-5 weeks before last frost, as soon as soil can be worked. |
| Turnip | — | Mar 29 – Apr 12 | — | Aug 13 – Aug 27 | 40–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. |
| Onion | Feb 15 – Mar 1 | — | Mar 29 – Apr 12 | — | 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 24 – Oct 8 | 240–270 days | Fall-planted crop only; not planted in spring in most climates. |
| Potato | — | Mar 29 – Apr 12 | — | — | 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 10 – May 24 | — | 90–120 days | Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive. |
| Asparagus | — | — | Mar 29 – Apr 12 | — | 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. |
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Basil | Mar 15 – Mar 22 | — | May 3 – May 10 | — | 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 5 – Apr 19 | — | Aug 27 – Sep 10 | 45–70 days | Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring. |
| Parsley | Mar 1 – Mar 15 | — | Apr 12 – Apr 19 | — | 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 5 – Apr 19 | — | — | 40–60 days | Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer. |
| Oregano | Mar 1 – Mar 15 | — | Apr 26 – May 3 | — | 80–90 days | Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date. |
| Thyme | Mar 1 – Mar 15 | — | Apr 26 – May 3 | — | 85–95 days | Perennial herb, slow from seed; start indoors 6-8 weeks before last frost, transplant around/after last frost. |
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Sunflower | — | May 3 – May 17 | — | — | 70–100 days | Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting. |
| Zinnia | Mar 29 – Apr 5 | May 3 – May 17 | May 3 – May 10 | — | 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 15 – Mar 29 | — | May 3 – May 10 | — | 45–60 days | Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed. |
| Cosmos | Mar 29 – Apr 5 | May 3 – May 17 | May 3 – May 10 | — | 60–90 days | Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early. |
| Nasturtium | — | May 3 – May 17 | — | — | 50–65 days | Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed. |
| Dahlia | — | — | May 3 – May 17 | — | 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 Troy, MI?
Based on 1991–2020 NOAA climate normals for the PONTIAC WWTP, MI US station, the last spring frost in Troy typically falls around April 26. A cautious gardener might wait until May 12 (only a 10% chance of a later frost), while April 15 marks an earlier, higher-risk planting date.
When is the first frost in Troy, MI in fall?
The first fall frost in Troy typically arrives around October 22. To stay safe, assume frost could start as early as October 7; in milder years it can hold off until November 4.
How long is the growing season in Troy, MI?
Troy's average frost-free growing season is about 177 days, running from the typical last spring frost (April 26) to the typical first fall frost (October 22).
What USDA hardiness zone is Troy, MI in?
Troy, MI is in USDA plant hardiness zone 6b, per the USDA's 2023 Plant Hardiness Zone Map. A classic four-season climate with cold winters and a solid summer growing season.