Start indoors or direct sow?

Direct sow kale for a simple crop, or start it indoors and transplant for an earlier harvest and more precise spacing. Kale transplants well when seedlings are young and not root-bound.

When to start Kale seeds

Start indoors 4 to 6 weeks before the last spring frost, or direct sow 2 to 4 weeks before the last frost. For fall crops, start or sow about 6 to 8 weeks before the first expected fall frost.

How to sow the seeds

Sow seeds 1/4 to 1/2 inch deep in sterile seed-starting mix in small cells, or sow directly into loose, fertile garden soil. Keep indoor containers warm enough for steady germination and use individual cells to minimize root disturbance.

Germination

Kale generally germinates in 5 to 10 days. Soil temperatures around 60 to 75 F with steady moisture give reliable results, though seeds can sprout in cooler soil.

Seedling care

Provide bright light indoors and water when the mix surface begins to dry, never leaving seedlings in standing water. Thin direct-sown plants to the variety's recommended spacing, and use airflow, clean mix, and good drainage to prevent damping off.

Transplanting & hardening off

Harden seedlings off for 5 to 7 days, then transplant before they become crowded in their cells. Plant at the same depth as the container soil and water well, even if light frost is still possible.

Tips

Start a small succession every few weeks for a longer leaf harvest. Protect seedlings from cabbage worms with row cover as soon as they are planted outside.

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