Start indoors or direct sow?

Direct sow is usually best because seeds are small, plants grow fast, and they do not need an indoor head start. Indoor starts are possible for an earlier crop, but use small cells and transplant young.

When to start Amaranth Greens seeds

Direct sow after the last spring frost, once soil has warmed to about 65 F or more. For transplants, sow indoors 3 to 4 weeks before the last frost and set plants out after frost danger has passed.

How to sow the seeds

Sow seeds 1/8 to 1/4 inch deep in finely prepared soil, or barely cover them in a sterile seed-starting mix. For indoor starts, use plug trays or small cells and bottom-water gently so the seeds are not displaced.

Germination

Germination usually takes 4 to 10 days at about 70 to 85 F. Keep the seedbed or mix evenly moist until seedlings are established, without leaving it soggy.

Seedling care

Give indoor seedlings strong light and thin direct-sown seedlings gradually to 6 to 12 inches apart, depending on whether you want baby greens or larger plants. Water gently, provide airflow, and avoid crowded, constantly wet seedlings to reduce damping off.

Transplanting & hardening off

If started indoors, harden seedlings off for 5 to 7 days and transplant after the last frost while they are still small. Space them 6 to 12 inches apart and water them in well.

Tips

Make several small sowings 2 to 3 weeks apart for a longer harvest. Do not let seedbeds crust over, since the very small seedlings need an easy path to the surface.

General seed-starting guidance for US home gardens; timing depends on your local frost dates and variety. Page updated Aug 4, 2026.