How to Grow Green Curled Ruffec Kale

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Green Curled Ruffec Kale

Brassica oleracea var. acephala

vegetable

Green Curled Ruffec is a cold-hardy kale variety prized for its deeply crimped, dark green leaves and exceptional flavor. This heirloom cultivar develops a rosette form and becomes sweeter after frost exposure. It's a staple in European cuisine and highly valued by gardeners for its productivity and ornamental appeal.

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Example Green Curled Ruffec Kale timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Green Curled Ruffec Kale

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Green Curled Ruffec Kale

    Around Jun 11

    ≈ 55 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Green Curled Ruffec Kale dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6+ hours daily (tolerates partial shade)
💧
Water: Consistent moisture; keep soil evenly moist but not waterlogged. Water deeply 1-2 times weekly. Drought stress reduces leaf quality.
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Spacing: 18 inches
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Days to maturity: 55-90 days (harvest begins sooner; improves with cool weather)
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Planting depth: 0.5 inches for seeds; transplants at same depth as in starter pot

Soil

Type: Well-draining loamy soil rich in organic matter
pH: 6.0-7.5
Amendments:
Compost aged manure fish emulsion kelp meal bone meal

Growing Zones

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Thrives in zones 3-9, with exceptional cold tolerance in zones 3-7

3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b

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Growth Stages

1

Seedling

2-3 weeks

Small plants with 2-4 true leaves, tender and delicate

Keep soil consistently moist. Provide bright light if indoors. Thin seedlings to proper spacing to prevent overcrowding and leggy growth.

2

Vegetative Growth

3-5 weeks

Rosette formation begins with multiple leaves unfurling from central stem; characteristic curl becomes more pronounced

Maintain consistent watering and nutrient levels. Apply balanced fertilizer or compost tea every 3-4 weeks. Monitor for pests. Mulch around base.

3

Leaf Development

3-6 weeks

Full rosette established with deeply crimped, dark green leaves reaching mature size and texture

Continue regular watering and feeding. Pinch off any flowering shoots to encourage leaf production. Begin harvesting outer leaves as needed.

4

Fall/Winter Enhancement

Variable, frost-dependent

Leaf color deepens and sweetness increases significantly after frost exposure; flavor peaks after 2-3 hard freezes

Reduce nitrogen fertilizer. Protect from extreme cold with row covers in zone 3-4. Light frosts actually improve taste and tenderness.

5

Harvest

8-16 weeks of continuous harvest

Plant produces harvestable leaves throughout season; center remains productive for months with proper leaf removal

Harvest outer leaves first, leaving inner leaves to continue growing. Can harvest individual leaves or cut whole plant 2 inches above soil for regrowth.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Tomatoes Pole beans Fennel Kohlrabi Strawberries Cabbage (too close) Broccoli (too close)

Common Pests

  • Row covers during egg-laying season, Bt (Bacillus thuringiensis) spray, hand-picking caterpillars, companion planting with chamomile

  • Neem oil, Bt spray, row covers, encouraging parasitic wasps with flowering plants

  • Row covers on young plants, neem oil, diatomaceous earth, kaolin clay spray

  • Strong water spray, insecticidal soap, neem oil, reflective mulches, beneficial insects

  • Yellow sticky traps, neem oil, insecticidal soap, reflective mulch

  • Crop rotation (3-year minimum), raise soil pH to 7.2+, remove infected plants, disinfect tools

Uses

🍳

Salads & Fresh Cooking

Culinary

Young, tender leaves are excellent raw in salads with a slightly spicy, complex flavor. Mature leaves are ideal for sautéing, steaming, or adding to soups, sauces, and grain bowls. The crimped texture holds dressings and sauces beautifully. [source]

💊

Nutritional Powerhouse

Medicinal

Exceptionally high in vitamins K, A, and C, as well as calcium, iron, and antioxidants including sulforaphane and lutein. Regular consumption supports bone health, immune function, and eye health. [source]

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Juice & Smoothies

Household

Nutrient-dense leaves are popular in green juice blends and smoothies. The mild flavor (especially in frost-sweetened winter leaves) makes it less bitter than some kale varieties. [source]

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Ornamental Gardening

Craft

With its striking deep green, heavily ruffled foliage, Green Curled Ruffec serves as both a productive food crop and beautiful ornamental plant. Popular in cottage gardens and edible landscaping. [source]

🦋

Pollinator Support

Wildlife

If left to bolt, kale produces abundant yellow flowers that attract bees and other pollinators. Excellent for supporting beneficial insects while extending garden aesthetics. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Begin harvesting outer leaves when plants are 8-10 inches tall, typically 50+ days from transplanting. Harvest leaves from bottom upward, leaving the growing center intact for continuous production. Pick leaves in early morning for best texture and flavor. Green Curled Ruffec becomes sweeter and more tender after light frosts (28-32°F). Can harvest continuously through winter in mild climates. In cold zones, harvest before hard freezes below 10°F; plants will survive but leaves become brittle.

Fun Facts

  • 🌱 Green Curled Ruffec is a heirloom variety originating in France (Ruffec region), cultivated for centuries and prized by European gardeners for superior cold hardiness and flavor complexity.
  • 🌱 Kale actually improves in taste after frost; sugars increase as the plant converts starch to sugar as a natural anti-freeze mechanism, making late-season harvests sweeter than early harvests.
  • 🌱 A single kale plant can produce harvestable leaves for 3-4 months or longer with proper leaf-removal technique, making it one of the most productive vegetables per plant for season-long harvests.

Gardening Terms

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