Sow at a depth of approx.
0.0 inches (0.0 cm) and aim for a distance of at least
5.85 inches (15.0 cm) between Snapdragon plants. Soil temperature should be kept higher than
13°C / 55°F to ensure good germination.
By our calculations, you should look at sowing Night and Day about 56 days before your last frost date.
As Night and Day is hardy, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.