Planting
Planting your garden in Michigan at the right time means the difference between a thriving 🌱 harvest and wasted effort—so timing your crops to match the 5b-6b frost dates is the key.
Michigan’s unpredictable spring weather can turn gardening dreams into nightmares if you plant too early—or wait too late. But timing your garden right means the difference between bumper crops and wasted seeds.
With last frosts creeping in as late as April 15 in some regions and first frosts arriving by October 15, knowing when to start seeds, transplant seedlings, and sow direct is critical for success.
Below, I break down the exact planting windows for cool-season crops like lettuce and spinach, warm-season favorites like tomatoes and peppers, and even fall planting tips to squeeze in a second harvest before winter sets in.
Michigan’s frost dates by region: when to plant cool vs warm-season crops
Michigan’s last frost dates vary dramatically from southern Detroit to northern Marquette, making timing your garden a critical skill.
In Detroit (Zone 6a), the average last frost arrives by April 20, while Traverse City (Zone 5b) waits until May 5, and Marquette (Zone 4b) often sees frost until May 20. These differences dictate whether your tomatoes or peppers thrive—or get fried.
Cool-season crops like lettuce and spinach can handle light frosts and should go in 4-6 weeks before your region’s last frost. Warm-season crops like tomatoes and peppers, however, need soil temps above 50°F and no frost risk, so wait until 2 weeks after your last frost date.
For example, Detroit gardeners can plant tomatoes May 5, while Marquette waits until June 5.
Use Michigan State University’s frost-date calculator to pinpoint your exact last frost date—but always have row covers ready for late surprises. I’ve planted basil too early in Traverse City only to watch it wilt under a May frost. Lesson learned: When in doubt, wait!
Here’s how Michigan’s four key regions break down for cool vs. warm-season crops, including planting windows and frost-free days:
| Region | Last Frost Date | First Frost Date | Cool-Season Start | Warm-Season Start | Frost-Free Days |
|---|---|---|---|---|---|
| Springfield (Zone 6a) | April 15 | October 20 | March 20 (hardy crops) | May 1 | 180 days |
| Detroit (Zone 6a) | April 20 | October 15 | March 25 (hardy crops) | May 5 | 175 days |
| Traverse City (Zone 5b) | May 5 | October 5 | April 10 (hardy crops) | May 20 | 150 days |
| Marquette (Zone 4b) | May 20 | September 25 | April 25 (hardy crops) | June 5 | 120 days |
For cool-season crops like kale, carrots, and peas, start seeds indoors 6-8 weeks before your last frost. In Detroit, that means February 20, while Marquette gardeners wait until April 1.
These crops tolerate light frosts (down to 25°F for kale), so you can plant them 2 weeks before your last frost date for an early harvest.
Warm-season crops like tomatoes, peppers, and cucumbers need warm soil (at least 50°F) and no frost risk. I’ve learned the hard way that planting tomatoes in
Best planting schedule for Michigan gardens: month-by-month crop timeline
Michigan’s growing season is short but sweet—getting your planting schedule right means the difference between a thriving garden and a wasted season. The key? Knowing when to plant each crop based on soil temperatures, frost dates, and succession planting strategies.
Below is my month-by-month guide for 12 essential crops, including cool-season stars like spinach and warm-season favorites like tomatoes.
For Michigan gardeners, timing is everything. Cool-season crops like peas and lettuce can handle late frosts, while warm-season crops like peppers and beans need soil temperatures above 60°F.
Use this schedule to maximize yields and extend harvests with succession planting. Pro tip: Always check your local last frost date—it varies by region!
- March: Plant spinach and peas under row covers when soil hits 35°F. Harden off cool-season transplants like broccoli.
- April: Sow lettuce, kale, and radishes as soon as soil is workable. Start tomato and pepper seeds indoors for May transplants.
- May: Transplant tomatoes, peppers, and eggplants after last frost (soil ≥ 60°F). Direct-sow beans, corn, and cucumbers.
- June: Succession plant bush beans and zucchini every 2 weeks. Start fall crops like carrots and beets for late harvests.
- July: Plant late-season potatoes and garlic for fall harvests. Direct-sow spinach for fall greens.
- August: Sow cool-season crops like radishes and turnips for early fall harvests. Transplant broccoli and cabbage.
- September: Extend harvests with succession plantings of lettuce and kale. Cover crops with row covers to delay frost.
Don’t let Michigan’s unpredictable weather derail your garden. For warm-season crops like tomatoes, wait until the soil temperature consistently stays above 60°F—usually mid-May. Use a soil thermometer to check, and avoid planting too early, or you’ll risk rotten seedlings.
For cool-season crops, like spinach, start seeds indoors in March and transplant after the last frost.
Succession planting is your secret weapon for nonstop harvests. For example, sow bush beans every 2 weeks from June to July to keep picking until fall frost.
Similarly, plant lettuce in early spring and again in late summer for a fall crop. This technique ensures you’re always eating fresh from your garden!
Pro tip: Use row covers or cold frames to extend your season. They protect cool-season crops from late frosts and warm-season crops from early chills. For example, I’ve kept spinach growing well into November with a simple floating row cover. It’s a game-changer for Michigan gardeners!
Remember, fall planting is just as important as spring. By August, you can still sow cool-season crops like kale and radishes for a harvest before winter.
These crops thrive in cooler weather and often taste sweeter after a light frost. Plan ahead, and you’ll enjoy homegrown veggies well into December!