Annuals: A Schedule

It is so hard to find a timeline for when to start seed for our most common annuals, and nearly impossible to find this information all in one place, where you can see what to do when at a glance. Well, In the Garden Online is here to help with a concise, clear chart for your annual seed-starting.

The dates on this chart are for the Tri-County Detroit area and most of the southern lower peninsula, based on a last frost date of anywhere from April 15th to May 1st. If you live in the northern Lower Peninsula, your schedule will be approximately two weeks later. If you live in the Upper Peninsula, it will be two to four weeks later. ITGO

Plant Description Height Start Seed Plant Outside
Ageratum Flowers look like small powder puffs in white, pink, mauve, or blue. 6" to 36" February 1st May 1st
Plant Description Height Start Seed Plant Outside
Alyssum Lacy mounds of small flower clusters with 1 to 2 inch blooms in pink, yellow, salmon, purple, or white. 3" to 12" March 1st May 1st
Plant Description Height Start Seed Plant Outside
Bachelor's Button Tall, think stems topped with 1 to 2 inch blooms in blue, violet, pink, white or red. 12" to 40" March 15th May 1st
Plant Description Height Start Seed Plant Outside
Begonia Good for shade, interesting foliage, 1/2" blooms in orange, red, yellow, pink, white or bicolor. 6" to 24" January 1st May 15th
Plant Description Height Start Seed Plant Outside
China Aster Single, double or semi double flowers in purple, pink, blue, red, peach, yellow or white. 6" to 36" March 15th May 15th
Plant Description Height Start Seed Plant Outside
Cockscomb Fuzzy, oddly shaped flowers in red, orange, yellow, pink and purple. 16" to 36" April 1st May 1st
Plant Description Height Start Seed Plant Outside
Coleus Foliage plant with wide variety of colors, from deep purple to chartreuse. Excellent for shade. 6" to 36" April 15th May 15th
Plant Description Height Start Seed Plant Outside
Cosmos Old-fashioned flower. Daisy-like blooms atop tall, thin stems. Blooms in pink, purple, white, yellow, orange, red, magenta and maroon. 1' to 7' March 15th May 15th
Plant Description Height Start Seed Plant Outside
Dusty Miller Fuzzy silvery-green foliage. 12" to 24" February 15th May 15th
Plant Description Height Start Seed Plant Outside
Geranium Single, double or semi-double blooms atop various kinds of foliage, from ivy-shaped to the traditional round fuzzy leaves. Blooms in red, pink, orange, purple, salmon and white. 8" to 36" December 15th May 1st
Plant Description Height Start Seed Plant Outside
Globe Amaranth Clover-like flowers in purple, orange, magenta, pink, white and red. 6" to 30" March 15th May 1st
Plant Description Height Start Seed Plant Outside
Heliotrope Tiny flowers with intense vanilla-like scent. Shrubby growth habit. Blooms in purple, blue or white. 8" to 4' January 15th May 15th
Plant Description Height Start Seed Plant Outside
Impatiens Prolific bloomers, great for shade. Cup-shaped flowers in purple, red, yellow, orange, apricot, magenta and white. 6" to 36" January 15th May 1st
Plant Description Height Start Seed Plant Outside
Lobelia Delicate flowers atop thin stems. Blooms in purple, pink, blue, white and red. 4" to 10" February 1st May 1st
Plant Description Height Start Seed Plant Outside
Marigold Blooms in yellow, red, orange, brown, cream and bicolor. 6" to 36" March 15h May 1st
Plant Description Height Start Seed Plant Outside
Petunia Trumpet shaped flowers in pink, purple, red, white, coral, yellow, blue and bicolor. 6" to 18" January 15th April 15th
Plant Description Height Start Seed Plant Outside
Salvia Spikes of small flowers in red, blue, purple, burgundy, pink, orange, yellow, cream and white. 1' to 4' March 1st May 1st
Plant Description Height Start Seed Plant Outside
Snapdragon Blooms are said to resemble dragons' heads. Blooms in white, cream, yellow, orange, red, maroon, pink and purple. 6" to 4' February 15th April 15th
Plant Description Height Start Seed Plant Outside
Sunflower Dwarf to giant varieties in yellow, brown and cream. 2' to 15' April 1st May 1st
Plant Description Height Start Seed Plant Outside
Verbena Small flowers clustered atop nondescript stems. Blooms in red, pink, purple, blue, yellow, magenta, peach and white. 8" to 5' February 15th April 15th
Plant Description Height Start Seed Plant Outside
Zinnia Single, double and semi double blooms in red, yellow, green, purple, orange, pink, white, maroon, brown and gold. 6" to 36" March 15th May 15th