Answer: I don't have your exact last frost date, but Detroit is usually around April 24. It's safe to plant most seeds outdoors after the last frost date, and after the soil warms up a bit. Plants that prefer cooler temperatures (root crops, greens, sweet peas) can be started sooner than those that prefer warmer temperatures (vining crops, zinnias). Check with your County Cooperative Extension office. They'll have the preferred planting times for your specific region. Plant cannas, dahlias and other tender bulbs in the garden about 2 weeks before your last frost date.
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