How to Grow Crimson Curls
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Crimson Curls
Brassica oleracea var. acephala
vegetableCrimson Curls is a striking red curly kale variety with deeply frilled, burgundy-colored leaves that become sweeter after frost exposure. This ornamental and edible brassica thrives in cool-season gardens and offers both visual appeal and nutritional value. The plant develops as a leafy rosette without forming a head, making it ideal for continuous harvesting.
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Example Crimson Curls timeline · Pittsburgh, PA (Zone 6b)
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Plant Crimson Curls
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Crimson Curls
Around Jun 11≈ 55 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Crimson Curls dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-9; prefers cooler temperatures in spring and fall
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Seedling
7-14 daysTiny cotyledons emerge; first true leaves are simple and smooth-edged. Plant is fragile and low to soil.
Keep soil consistently moist but not waterlogged. Provide 12-16 hours of light. Maintain 60-70°F temperatures. Thin seedlings to prevent crowding.
Vegetative
3-5 weeksPlant develops increasingly ruffled, deeply curled leaves with deep red coloring. Rosette expands outward. Plant height reaches 12-18 inches.
Apply consistent moisture and fertilize every 2-3 weeks with balanced or nitrogen-heavy fertilizer. Keep soil rich with compost. Monitor for pests like cabbage loopers.
Maturation
2-4 weeksCurly leaves reach full size and vibrant crimson coloring deepens. Plant fills out its mature rosette form, 18-24 inches tall and wide.
Continue consistent watering and light feeding. Leaves are harvestable at any point. Cold temperatures enhance sweetness by converting starches to sugars.
Peak Harvest
4-8 weeks or until frost/heat stressLeaves are full-sized, deeply curled, and richly colored. Plant continues producing new center growth even as outer leaves are removed.
Harvest outer leaves regularly to encourage continuous production. Pinch off any flower buds to extend leaf production. Plant improves with light frost.
Cold Hardiness
Variable; extends season significantlyPlant becomes even sweeter and more tender after freezing temperatures. Can often survive harsh winters in colder zones.
Light frost (down to 20°F) improves flavor. Plant may overwinter in mild climates. In cold zones, may produce into winter or spring depending on timing.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick caterpillars; use row covers on young plants; apply Bt (Bacillus thuringiensis) if infestation is heavy; encourage parasitic wasps
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Use floating row covers; apply Bt spray; handpick eggs from leaf undersides; plant marigolds and nasturtiums as trap crops
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Apply diatomaceous earth; use row covers on seedlings; spray neem oil if severe; mulch heavily to disrupt breeding
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Strong water spray to dislodge; sticky yellow traps; reflective mulches; neem oil spray on leaf undersides
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Spray with strong water stream; insecticidal soap; neem oil; encourage ladybugs and parasitic wasps
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Rotate crops; raise soil pH to 7.2+; avoid planting other brassicas nearby; remove infected plants immediately
Uses
Raw salads and slaws
CulinaryYoung, tender Crimson Curls leaves are delicious raw in salads, adding a crisp texture and mild, slightly sweet kale flavor with beautiful red coloring. The decorative curled leaves also serve as an elegant salad base. [source]
Cooked greens and smoothies
CulinaryMature leaves are excellent steamed, sautéed, or added to soups and stews, becoming tender when cooked. Rich, nutritious smoothies benefit from the mild flavor of Crimson Curls compared to other kale varieties. [source]
Nutritional powerhouse
MedicinalCrimson Curls is extremely high in vitamins A, C, K, calcium, and antioxidants. The red pigmentation indicates anthocyanins, powerful anti-inflammatory compounds linked to improved heart and brain health. [source]
Ornamental garnish and display
HouseholdThe striking deep red, ruffled foliage makes Crimson Curls an attractive ornamental plant for decorative garden beds or containers. Leaves also serve as beautiful, edible garnishes for platters and dishes. [source]
Pollinator and beneficial insect support
WildlifeIf allowed to flower, kale produces yellow blooms attractive to bees and other pollinators. The plant's structure also provides shelter for beneficial insects that help control garden pests. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Harvest outer leaves individually once plant is 12+ inches tall, leaving 4-5 inches of stem to continue growing. Pick leaves in the morning after dew dries for best quality. Tender inner leaves can be harvested at any size. Plant continues producing for weeks to months with regular harvesting. Flavor sweetens dramatically after a light frost; cold improves texture and taste.
Fun Facts
- 🌱 Crimson Curls' red color intensifies and becomes sweeter after exposure to freezing temperatures—a process where plant cells convert starches to sugars as a natural antifreeze, making winter-harvested kale a delicacy.
- 🌱 Kale is one of the most nutrient-dense foods available per calorie, containing more vitamin K per serving than almost any other food; one cup provides over 1000% of the daily recommended value.
- 🌱 Crimson Curls is a non-heading variety of kale, meaning it produces leaves continuously without forming a tight head like cabbage, allowing for months of harvesting from a single plant.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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