Aim to sow
0.2 inches (0.5 cm) deep and try to ensure a gap of at least
1.95 inches (5.0 cm). Soil temperature should be kept higher than
18°C / 64°F to ensure good germination.
By our calculations, you should look at sowing Corcel about 38 days before your last frost date.
As Corcel is tender, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.