Sow at a depth of approx.
0.0 inches (0.01 cm) and aim for a distance of at least
11.7 inches (30.0 cm) between Coleus plants. Soil temperature should be kept higher than
65°C / 149°F to ensure good germination.
By our calculations, you should look at sowing Haines about 56 days before your last frost date.
As Haines is tender, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.