Winterbor (F1) Kale

(Brassica oleracea var. sabellica)

Winterbor (F1) Kale is a hardy, curly-leaf kale variety known for its cold tolerance, vigorous growth, and excellent flavor. This hybrid produces dense, ruffled blue-green leaves that become sweeter after exposure to frost. Winterbor is a favorite for fall and winter gardens, providing nutritious greens long after many other crops have stopped producing.

Plant Specifications

Common Name: Winterbor Kale
Scientific Name: Brassica oleracea var. sabellica
Variety Type: Hybrid (F1)
Plant Type: Cool-season leafy vegetable
Plant Height: 24–36 inches
Spread: 18–24 inches
Sunlight: Full sun to partial shade
Soil: Rich, well-drained soil with organic matter
Water Needs: Moderate; consistent moisture improves leaf quality
Days to Harvest: Approximately 55–65 days
Leaf Color: Blue-green
Leaf Type: Curly, ruffled

Growing Tips

• Plant in early spring or late summer for fall and winter harvests.

• Kale thrives in cool temperatures and can tolerate frost.

• Regular harvesting of outer leaves encourages continuous production.

• Adding compost helps support strong, leafy growth.

Pollinator & Garden Value 🌼

Kale is usually harvested before flowering, but if allowed to bolt, it produces tall yellow flowers that attract:

• Bees

• Butterflies

• Beneficial insects

These blooms support pollinators early in the season.

Interesting Facts

• Kale becomes sweeter after frost because cold temperatures convert starches into sugars.

• It is considered a superfood, rich in vitamins A, C, and K, as well as antioxidants.

• Kale belongs to the same species as cabbage, broccoli, and Brussels sprouts.

• It can survive temperatures well below freezing, making it one of the hardiest garden greens.

Garden Learning Connection 🌱

At the Thorn Hill Education Center Garden, Winterbor kale demonstrates how cold-hardy crops extend the growing season. Visitors can scan the QR code near the plant to learn about seasonal planting, plant resilience, and how leafy greens can be harvested over time for continuous food production.