Mustard is cool-season leaf crop. Sow mustard as early as 4 to 6 weeks before the average last frost date in spring. Sow succession crops every 4 to 6 weeks. Mustard requires 30 to 40 days to reach harvest. Plant crops so that they come to harvest before temperature average greater than 75°F. Sow mustard in autumn or early winter in mild winter regions.
Seeds may be slow to germinate if the soil is too cool, 40°F or less. Mustard grown in hot weather or long days will bolt and go to seed.
Sow mustard seed1/2" deep, when seedlings are large enough to handle thin them from 4"- 9" apart, space rows 12"-24" apart.
Keep soil evenly moist to keep leaves growing quickly. Do not allow the soil to dry out. Add aged compost to planting beds before sowing. Side dress plants with aged compost at midseason.