How to Grow Kale
Brassica oleracea var. sabellica
Kale is a hardy brassica valued for its nutritious leaves and ability to thrive in cool weather. Gardeners prize this versatile crop for its resilience against light frosts and its suitability for both fresh eating and winter storage.
📷 Wikipedia: KaleStarting Kale: indoors or direct sow?
🏠 Start indoors 4 weeks before your last spring frost, then move the seedlings outside.
If starting indoors, harden off seedlings gradually before moving them outdoors two to six weeks prior to the last frost date.
Soil, care & harvest
Prepare loose, fertile soil with a pH between 6.0 and 7.5. Sow seeds directly outdoors or start indoors two to six weeks before the last spring frost. Press seeds lightly into the soil at a depth of about one inch, as they germinate within five to eight days once conditions are right.
Space plants twelve to eighteen inches apart to ensure good air circulation. Provide moderate watering, aiming for one to one-and-a-half inches per week. Apply mulch around the base to retain moisture and suppress weeds, while feeding regularly with a balanced fertilizer to support steady growth throughout the season.
Watch for common brassica pests like cabbage loopers and caterpillars; hand-pick them or use row covers for prevention. Diseases such as clubroot can occur in wet soils, so ensure proper drainage. Harvest outer leaves fifty to sixty-five days after sowing by snipping them at the base, allowing the plant to continue producing new growth.
When to Plant Kale
Planting windows vary by USDA hardiness zone. Look up yours by ZIP code.
| Zone | Start Indoors | Direct Sow | Harvest |
|---|---|---|---|
| Zone 1 | April – May | June – July | August – September |
| Zone 2 | April – May | May – July | July – September |
| Zone 3 | March – April | May – June | July – October |
| Zone 4 | March – April | April – June | July – October |
| Zone 5 | February – March | April – May | June – November |
| Zone 6 | February – March | April – May | June – November |
| Zone 7 | February – March | March – May | May – November |
| Zone 8 | January – February | March – April | May – December |
| Zone 9 | January | February – March | April – December |
| Zone 10 | January | January – March | March – December |
| Zone 11 | January | January – February | February – December |
| Zone 12 | January | January – February | February – December |
| Zone 13 | January | January – February | February – December |
