Early Seed Starting — Waiting for a Warm Up

Lettuce seedlings

Tom’s trays of lettuce are ready for the cold frame, if it ever warms up.

I started lettuce early this year—on February 22—so that we would be able to display the new seedlings in our exhibit at the Minneapolis Home & Garden Show. Using the weather patterns of the last few years as a guide, I was confident that once we were midway through March the nighttime temperatures would be warm enough to that I could move the trays outdoors and into some cold frames we have behind our office, until they were ready to be planted in the garden.

That didn’t happen.

lettuce closeInstead of nighttime lows above 20 degrees F, the temps have been hovering in the low teens—too cold for lettuce, even in a cold frame. Saturday night’s low is predicted to be 8 degrees, and Monday’s is 7. Now I’ve got a dozen trays of lettuce starts bursting from their containers and ready to harvest. The folks in my office will be enjoying some spring salads before it’s even officially spring.

These are 12 different varieties, which I started in plastic trays from cookies and other baked goods. Lettuce sprouts quickly, within a couple of days, and germinates at lower temperatures than many other seeds. You don’t need to put a heat mat under the tray or do anything special other than provide a source of light. I use grow lights—other people start lettuce in a sunny window.

I’ve also started a tray of pepper and eggplant varieties, but nothing has germinated yet.  Yesterday I started three trays of heirloom tomatoes—nearly 60 varieties. I’m trying hard to limit the number of tomato varieties I’ll grow this year to 80, but right now that’s looking doubtful. Next week I’ll start herbs and flowers—a tray of each.

For me, the day I first start seeds is the best day of the year.

What seeds will you be starting this season?

—Tom McKusick

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