These are a few of the easiest, most prolific and popular "volunteer" flowers — annuals that die by summer's end but produce seeds that will take root the following spring.

1. Johnny-Jump-Up (Viola tricolor)
Low mounds of three- to five-inch-tall, small, pansylike flowers; good edging plant; full sun or partial shade.

2. Tall Verbena (Verbena Bonariensis)
Clusters of tiny purple flowers float above tall, wiry stems three to six feet tall; full sun.

3. Cosmos (Cosmos Bipinnatus)
Tops out at three to four feet high; colors range from pinks to crimson to white; full sun.

4. Foxglove (Digitalis purpurea)
Clusters of bell-shape flowers grow along a three- to six-foot-tall stalk; colors range from purples to pinks to white; full sun or partial shade.

5. Corn Poppy (Papaver Rhoeas)
Cup-shape flowers grow to two feet tall; doesn't like transplanting; full sun.

6. Love-in-a-Mist (Nigella Damascena)
Small blue blossoms float in drifts of delicate foliage up to two feet tall; can be dried; full sun.

7. Black-Eyed Susan (Rudbeckia Hirta)
Daisylike flower heads on stems one to three feet tall; full sun or partial shade.

8. Feverfew (Tanacetum Parthenium)
Bushy clumps up to two feet tall covered with tiny, daisylike flowers (also comes in a golden-leaved variety, 'Aureum'); full sun.

9. Spider Flower (Cleome Hassleriana)
Grows three to five feet tall with impressive white, pink, or purple fragrant flowers; full sun.