Keep in mind when planting that Blue Streak is thought of as half hardy, so remember to protect this plant from frosts and low temperatures.
Try to aim for a seed spacing of at least
11.7 inches (30.0 cm) and sow at a depth of around
0.04 inches (0.1 cm). Soil temperature should be kept higher than
18°C / 64°F to ensure good germination.
By our calculations, you should look at sowing Blue Streak about 56 days before your last frost date.
As Blue Streak is half hardy, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.