How to Grow Collard Greens
A Complete Guide from Planting to Harvest
Introduction to Collard Greens
Collard greens are one of the oldest members of the cabbage (Brassicaceae) family. Their species name is Brassica oleracea, the same as kale, cabbage, cauliflower, and broccoli. Unlike their relatives, collards don’t form a head – instead, they produce large, leafy green foliage.
A popular staple in Southern cuisine, collard greens are not only delicious but also packed with nutrients. They’re an excellent source of Vitamins A and C, iron, magnesium, calcium, and potassium, making them a nutritional powerhouse in your garden.
Collards are biennial plants in moderate climates but are typically grown as annuals. They’re remarkably cold-hardy, with some varieties surviving temperatures as low as 15°F (-9°C), making them perfect for fall and winter gardens.
Popular Varieties
Champion
A bolt-resistant variety with good cold resistance and attractive blue-green foliage. Perfect for gardeners in variable climates.
Morris Heading
Provides large, broad leaves and may form loosely arranged heads. Great for gardeners looking for abundant harvests.
Top Bunch 2.0
A hybrid with medium-sized, lightly savoyed leaves. Both attractive and tasty, making it a popular choice for home gardens.
Georgia Southern
A classic favorite with smooth leaves and white stalks. Can reach up to 6 feet tall, so give it plenty of space to grow.
Pro Tip:
If planting in spring (versus fall), choose a bolt-resistant variety like Champion to prevent early flowering.
When to Plant Collard Greens
Spring Planting
- Start seeds indoors 4-6 weeks before your last spring frost date
- Direct-sow seeds outdoors 2-4 weeks before your last spring frost
- Set out transplants 3-4 weeks before the last frost
- Choose bolt-resistant varieties for spring planting
Fall Planting (Preferred)
- Direct-sow seeds 6-8 weeks before the first fall frost
- Set out transplants 6-8 weeks before the first frost
- Fall planting often produces sweeter leaves as frost improves flavor
- In zones 8 and warmer, collards can provide harvests throughout winter
Climate Considerations:
Collards grow best in temperatures between 55°F and 75°F (13°C to 24°C). They can tolerate temperatures down to 15°F (-9°C) once established, making them excellent cool-season crops.
Site Selection & Soil Preparation
Ideal Growing Conditions
- Sunlight: Full sun (6+ hours) preferred, but will tolerate partial shade in hot climates
- Water Access: Choose a location with easy access to water
- Air Circulation: Good air flow helps prevent disease
- Space: Allow room for plants to reach their full size (up to 3 feet tall for some varieties)
Soil Requirements
- pH Level: 6.5 to 6.8 (slightly acidic)
- Soil Type: Well-drained, loamy soil preferred
- Organic Matter: Add compost or well-rotted manure
- Drainage: Ensure good drainage to prevent root rot
Soil Preparation Steps
Remove debris and weeds
Clear the planting area of rocks, sticks, and weeds. Collards have shallow roots and compete poorly with weeds.
Test soil pH
Use a soil test kit to check pH levels. Adjust with lime to raise pH or sulfur to lower it if needed.
Add organic matter
Mix in 2-3 inches of compost or aged manure to improve soil structure and fertility.
Apply balanced fertilizer
Work in a balanced fertilizer (10-10-10) according to package directions before planting.
Planting Methods
Direct Sowing Seeds
- Depth: ¼ to ½ inch deep
- Spacing: 3 inches apart
- Row Spacing: 18-36 inches between rows
- Germination: 5-10 days
- Thinning: When seedlings reach 4-5 inches tall, thin to 18-24 inches apart
Keep soil consistently moist during germination. Cover with row cover if pest pressure is high.
Transplanting Seedlings
- When: After seedlings have 4-5 true leaves
- Hardening Off: 7-10 days before transplanting
- Spacing: 18-24 inches apart
- Row Spacing: 18-36 inches between rows
- Planting Depth: Same depth as in containers
Water thoroughly after transplanting. Add a diluted fertilizer solution to reduce transplant shock.
Container Growing
- Container Size: At least 12 inches deep and 12 inches in diameter per plant
- Soil: High-quality potting mix with added compost
- Drainage: Ensure containers have drainage holes
- Spacing: One plant per 12-inch container; two plants per 18-inch container
- Watering: More frequent than garden plants; check daily in warm weather
Care & Maintenance
Watering
- Provide 1-1.5 inches of water per week
- Maintain consistent soil moisture
- Water at the base to keep leaves dry
- Morning watering is best
- Use mulch to retain moisture and reduce watering needs
Fertilizing
- Apply balanced fertilizer (10-10-10) at planting time
- Side-dress with nitrogen-rich fertilizer or compost every 3-4 weeks
- Collards are heavy feeders, especially for nitrogen
- Blood meal is excellent for boosting leaf growth
- Fish emulsion works well for container plants
Mulching
- Apply 2-3 inches of organic mulch around plants
- Use straw, shredded leaves, or grass clippings
- Keep mulch 1 inch away from stems
- Replenish mulch as it decomposes
- Mulch helps suppress weeds and maintain soil temperature
Weed Control
- Remove weeds regularly, especially when plants are young
- Hand pull weeds to avoid damaging shallow collard roots
- Use mulch to suppress weed growth
- Consider using a hoe for weeds between rows
- Keep a 2-foot perimeter around plants weed-free
Companion Planting Tip:
Collards grow well alongside aromatic herbs like thyme, mint, and rosemary, which can help repel pests. They also pair well with onions, garlic, and marigolds. Avoid planting near strawberries, tomatoes, or pole beans.
Pest & Disease Management
Common Pests
Cabbage Loopers & Cabbage Worms
Signs: Holes in leaves, green caterpillars
Control: Handpick, apply Bt (Bacillus thuringiensis), use row covers, attract beneficial insects
Aphids
Signs: Clusters of small insects, curled leaves, sticky residue
Control: Strong water spray, insecticidal soap, neem oil, encourage ladybugs
Flea Beetles
Signs: Small holes in leaves, tiny jumping insects
Control: Row covers, diatomaceous earth, sticky traps, keep garden clean
Slugs & Snails
Signs: Ragged holes in leaves, slime trails
Control: Beer traps, copper tape, diatomaceous earth, handpick at night
Common Diseases
Clubroot
Signs: Stunted growth, wilting, swollen roots
Control: Maintain soil pH 6.5-6.8, practice crop rotation, improve drainage
Black Rot
Signs: Yellow v-shaped lesions on leaf edges, blackened veins
Control: Use disease-free seeds, practice crop rotation, remove infected plants
Downy Mildew
Signs: Yellow patches on leaf tops, gray mold underneath
Control: Improve air circulation, avoid overhead watering, copper fungicide
Powdery Mildew
Signs: White powdery spots on leaves
Control: Neem oil, sulfur spray, baking soda solution, remove affected leaves
Organic Pest Control Spray:
Mix 1 tablespoon neem oil, 1 teaspoon mild liquid soap, and 1 quart of water. Spray on plants in the evening, coating both sides of leaves. Reapply weekly and after rain.
Harvesting Collard Greens
When to Harvest
- Begin harvesting when leaves reach 8-10 inches in length
- Most varieties mature in 60-80 days from seed
- Young, tender leaves have the best flavor
- Harvest before leaves become tough or stringy
- Frost-kissed leaves often taste sweeter (after light frost)
- Harvest in the morning when leaves are crisp
Mature collard greens ready for harvesting
Harvesting Techniques
Cut-and-Come-Again Method (Recommended)
Harvest the outer, lower leaves first and leave the center growth point intact.
- Use clean, sharp scissors or pruning shears
- Cut leaves 2 inches above the soil line
- Take only a few leaves from each plant
- New leaves will continue to grow from the center
- Can provide harvests for months with this method
Whole Plant Harvest
Cut or pull the entire plant when it reaches full maturity.
- Cut the stem 2 inches above the soil line
- Best when you need a large quantity at once
- Ideal for end-of-season harvest
- In mild climates, plant may regrow from the stub
- Allow some plants to flower for seed collection
Harvesting Tip:
For continuous harvests throughout the season, plant new collard greens every 2-3 weeks. This succession planting ensures you’ll always have tender young leaves available.
Post-Harvest Handling & Storage
Cleaning Collard Greens
Fill sink with cold water
Use a clean sink or large basin filled with cold water.
Submerge and swish
Dunk greens completely and swish gently to remove soil and insects.
Inspect and repeat
Check for remaining dirt or insects; repeat washing if necessary.
Dry thoroughly
Use a salad spinner or clean kitchen towels to remove excess water.
Storage Methods
Refrigerator Storage (Short-term)
- Wrap cleaned, dry leaves in paper towels
- Place in a perforated plastic bag
- Store in refrigerator crisper drawer
- Stays fresh for 5-7 days
Freezing (Long-term)
- Blanch leaves for 2 minutes in boiling water
- Cool quickly in ice water
- Drain and pack in freezer bags
- Remove excess air
- Keeps for up to 12 months
Cooking Tip:
Traditional Southern-style collards are simmered with smoked meat for 1-2 hours until tender. For a quicker preparation, remove the tough center stems, chop leaves into ribbons, and sauté with garlic and olive oil for 5-7 minutes.
Collard Greens Growing Timeline
Days 1-10: Germination
Seeds germinate in 5-10 days. Keep soil consistently moist but not soggy.
Days 10-30: Seedling Stage
First true leaves develop. When seedlings reach 4-5 inches tall, thin to final spacing.
Days 30-45: Early Growth
Plants begin to establish and grow more vigorously. Start regular fertilizing schedule.
Days 45-60: Leaf Development
Leaves expand and multiply. Watch for pests and diseases at this stage.
Days 60-80: Early Harvest
Begin harvesting outer leaves. Continue fertilizing to support new growth.
Days 80-120: Peak Production
Plants reach full size. Regular harvesting encourages continued leaf production.
Beyond 120 Days: Extended Harvest or Flowering
In cool weather, plants continue producing. In warm weather, they may begin to flower (bolt).
Troubleshooting Common Issues
Yellowing Leaves
Possible Causes:
- Nitrogen deficiency
- Overwatering
- Poor drainage
- Disease
Solutions: Apply nitrogen-rich fertilizer, improve drainage, check for signs of disease, adjust watering schedule.
Bolting (Premature Flowering)
Possible Causes:
- Hot weather
- Long daylight hours
- Plant stress
- Age of plant
Solutions: Plant bolt-resistant varieties, provide shade in hot weather, harvest before bolting begins, plant succession crops.
Stunted Growth
Possible Causes:
- Compacted soil
- Nutrient deficiency
- Root damage
- Clubroot disease
Solutions: Loosen soil, add compost, fertilize appropriately, check for pests damaging roots.
Bitter Taste
Possible Causes:
- Heat stress
- Old leaves
- Variety characteristics
- Growing conditions
Solutions: Harvest younger leaves, grow in cooler weather, try different varieties, blanch leaves in boiling water before cooking.
Conclusion
Growing collard greens is a rewarding experience that provides nutritious, versatile greens for your table. With proper care and attention to the guidelines in this guide, you can enjoy abundant harvests of these nutritional powerhouses. Remember that collards are one of the most cold-hardy vegetables in the garden, making them perfect for extending your growing season into fall and winter.
Whether you’re growing collards in a traditional garden, raised beds, or containers, these adaptable plants will reward you with delicious leaves that can be used in a variety of recipes. From traditional Southern-style slow-cooked greens to quick stir-fries, collards are a versatile addition to any kitchen.
As you gain experience with growing collard greens, you’ll discover the varieties and techniques that work best in your particular climate and garden. Don’t be afraid to experiment and adapt these guidelines to suit your specific conditions. Happy Gardening…
