Start seeds indoors 4/15-5/15 at around 70°. Cover seeds lightly with soil (plant seeds about 1/8" deep). Days to germination: 7-10. Transplant outdoors after the last frost (late May/early June). Plant spacing: 9-12". Alternatively, sow seeds outside early June.
For long lasting cut flowers, snip stem when petals begin opening but before they have opened completely.
Collect seeds by hand late summer. Birds love cosmos seeds so get them before the birds get them all! Use a fan to winnow out some of the debris.
