Freighter View Farms | Chris Izworski

There is a particular kind of gardening that belongs to the Great Lakes. It is not the long, forgiving season of the South, nor the cool predictability of the Pacific Northwest. It is a gardening shaped by lake-effect snow, by springs that arrive late and leave early, by summers that blaze hot and humid off the water, and by autumns so beautiful they make you forget that winter is already sharpening its teeth.

I garden in Bay City, Michigan, on the western shore of Saginaw Bay—part of the vast inland sea that is Lake Huron. My garden sits in USDA Zone 6a, which means winter lows between negative ten and negative five degrees Fahrenheit. That number shapes everything: what I plant, when I start seeds, how I protect tender transplants, and which varieties earn a permanent place in my seed collection.

What Zone 6a Means for a Michigan Garden

Zone 6a is the knife’s edge of Great Lakes gardening. We get roughly 150 to 170 frost-free days, depending on the year and how close you are to the water. My last spring frost typically falls in mid-May; the first fall frost arrives in early to mid-October. That is a tight window for warm-season crops like tomatoes, peppers, and melons—tight enough that starting seeds indoors is not optional. It is essential.

I start my tomato and pepper seeds under grow lights in early to mid-March, a full eight weeks before the last frost. By late April, the seedlings are hardening off on the porch, getting their first taste of real Michigan wind. By mid-May, if the forecast cooperates, they go into raised beds that have been warming under black plastic mulch since April.

Saginaw Bay: The Garden’s Silent Partner

The bay is not just a backdrop—it is an active participant in the garden. Lake-effect moisture softens our summers and moderates our falls, often giving us an extra two or three weeks of frost-free growing compared to inland areas. But the bay also brings morning fog that can slow tomato ripening and encourage fungal diseases if you are not careful about air circulation and plant spacing.

I have learned to work with the bay rather than against it. Vertical growing maximizes air flow. Single-stem tomato pruning keeps foliage open and light-penetrated. And I choose varieties that are proven performers in humid, Great Lakes conditions—not just catalog favorites from drier climates.

What Grows Well on Saginaw Bay

After years of trial, error, and careful seed saving, here is what thrives in my Zone 6a garden on the bay:

Tomatoes: Brandywine, Cherokee Purple, Mortgage Lifter, Sun Gold, and Costoluto Fiorentino have all earned their place. I grow them as single-stem plants in raised beds, pruned carefully and supported on tall stakes.

Peppers: Shishito peppers love our humid summers. They produce prolifically from July through the first frost, and their seeds save beautifully for the next season.

Cool-season crops: Radishes, kale, Swiss chard, lettuce, carrots, and broccolini are the backbone of my spring and fall gardens. Carrots, in particular, sweeten after a light frost and can be harvested well into November.

Herbs: Basil, dill, cilantro, and parsley are annuals that reseed themselves if you let them. Rosemary and thyme overwinter in sheltered spots with good drainage.

Flowers: Zinnias, cosmos, marigolds, globe amaranth, and sunflowers bring pollinators to the garden and seeds for next year’s beds. I save seeds from all of them.

The Seed Saving Advantage

Every year, my saved seeds perform a little better than they did the year before. That is not magic—it is selection. When I save seeds from the tomato that ripened earliest, the pepper that produced most heavily, the zinnia that bloomed longest, I am slowly adapting my garden to this specific place. The seeds carry the memory of this soil, this light, this lake air. No catalog seed can offer that.

That is the quiet power of seed saving in a Great Lakes garden: you are not just growing food. You are growing a garden that knows where it lives.

For more on my approach to seed saving, see the Complete Guide to Seed Saving for Beginners, or explore the full Michigan Zone 6a Garden Planner.

— Chris Izworski, Freighter View Farms, Bay City, Michigan

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