Sow at a depth of approx.
0.25 inches (0.64 cm) and aim for a distance of at least
0.98 inches (2.5 cm) between Garden Cosmos plants. Soil temperature should be kept higher than
20°C / 68°F to ensure good germination.
By our calculations, you should look at sowing Cosmos Polidor about 28 days before your last frost date.
As Cosmos Polidor is tender, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.
The botanical epithet is from the Latin bipinnatus meaning “staunch” or “like two small wings”.