How to Start Mustard Greens From Seed
Mustard greens grow quickly and are especially suited to cool spring and fall conditions. They are easy from seed and can be harvested young as baby greens or grown for full-sized leaves.
Start indoors or direct sow?
Direct sowing is usually easiest because mustard grows quickly, though indoor starts can provide an early crop. Seedlings transplant best while small and before warm weather accelerates bolting.
When to start Mustard Greens seeds
Direct sow 2 to 4 weeks before the last spring frost, then repeat every 1 to 2 weeks while weather remains cool. For transplants, start indoors about 3 to 4 weeks before the last frost and move them out 1 to 2 weeks before the frost date.
How to sow the seeds
Sow seeds 1/4 inch deep in a fine, moist seed-starting mix or directly in well-prepared garden soil. For transplants, use small cell trays and sow one or two seeds per cell; for baby greens, sow more densely in a shallow tray or bed.
Germination
Seeds often germinate in 4 to 8 days. Keep soil or mix evenly moist at about 60 to 75 F, without saturating it.
Seedling care
Give seedlings bright light and moderate watering, allowing the surface to dry slightly between waterings. Thin garden plants to about 4 to 6 inches for leaf harvest, or wider for larger plants, and provide airflow to reduce damping off indoors.
Transplanting & hardening off
If started indoors, harden seedlings off for about a week before planting. Transplant small plants at the same depth as their cells, about 4 to 6 inches apart, and water them in well.
Tips
Sow in partial shade as temperatures rise to slow bolting. Harvest outer leaves regularly, or cut baby leaves above the growing point for possible regrowth.
General seed-starting guidance for US home gardens; timing depends on your local frost dates and variety. Page updated Aug 4, 2026.