Sow at a depth of approx.
0.51 inches (1.3 cm) and aim for a distance of at least
5.85 inches (15.0 cm) between Broccoli plants. Soil temperature should be kept higher than
10°C / 50°F to ensure good germination.
By our calculations, you should look at sowing Red Spear about 42 days before your last frost date.
Ensure that temperatures are mild and all chance of frost has passed before planting out, as Red Spear is a tender plant.