Collard Greens (Brassica oleracea Acephala Group)
2 sources cited · Verified
The short answer
- Site
- 6+ hours of sun, soil pH 6–6.5
- Biggest risk
- Club root
Collard greens (Brassica oleracea Acephala Group) — biennial grown as an annual.
This crop carries an unusually heavy problem load: 2 diseases, 4 pests and 0 nutrient issues are documented for it, so most of the effort in growing it well goes into prevention.
Core growing advice on this page is checked against named horticultural and university-extension sources — see References.
Diseases
Pests
Quick Facts
| Factor | Value |
|---|---|
| Soil pH | 6 - 6.5 |
| Sunlight | 6-6 hours direct sun |
| Soil texture | well-drained, rich in organic matter; loam for best yields (NC State) |
| Drainage | well-drained |
| Lifecycle | biennial grown as an annual |
| Edible parts | leaves |
At a Glance
Soil & Growing Conditions
Water: moist but not saturated, especially during germination (NC State)
Soil pH range
Span reflects genuine variation between the cited authorities, not a single agreed figure.
Growth Stages
| Stage | BBCH | Notes |
|---|---|---|
| Sowing | 0 | Sow 1/2 to 3/4 inch deep in early spring or midsummer; keep the top 3/4 inch of soil moist but not saturated during germination (NC State). |
| Transplanting / thinning | 3 | Transplant or thin to spacing matching the intended harvest stage: 2-4in for young leaves, 10-15in for half-grown, 15-18in for full-grown plants (NC State). |
| Leaf growth | 4 | Cold-hardy and heat-tolerant, growing well across regions; needs ample nitrogen for deep green colour and tender growth (NC State, UMD Extension). |
| Harvest | 8 | Ready 60-80 days after sowing; harvest whole plants at any stage or pick individual leaves from mature plants -- flavour sweetens after frost (UMD Extension, NC State). |
Harvest & Storage
When to pick: Ready 60-80 days after sowing (UMD Extension). Cut whole young plants (which regrow), half-grown or full-grown plants, or harvest tender leaves individually from a mature plant (NC State). Flavour turns sweeter after a few frosts.
Collard Greens, Leaf to Harvest
References
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Cool-season crop thriving in early spring or fall. Sow seeds in early spring or midsummer; transplant in early spring or late summer. Plant seeds 1/2 to 3/4 inch deep, never deeper than 1 inch. Spacing varies by harvest maturity: young harvest 2-4in apart, half-grown harvest 10-15in apart, full-grown harvest 15-18in apart; optimal bed configuration two to four plants wide with 12-18in between beds. Soil pH 6.0-6.5, well-drained, rich in organic matter; loamy soils give greatest yields, sandy soils suit early spring crops; incorporate 2 inches of compost seven days before planting; needs ample nitrogen for deep green colour and tender growth. Mature plant tolerates frosts and light to medium freezes. Harvest: cut entire young plants (which regrow for multiple harvests), half-grown plants, full-grown plants, or harvest tender leaves individually from mature plants. Keep top 3/4 inch of soil moist but not saturated during germination. Notable NC-performing varieties: Vates, Carolina Improved Heading, Georgia Southern, Blue Max, Heavi Crop. Pests/diseases not addressed in this document.
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country=USA
2 independent sources are cited for this crop. Where they disagree - soil pH is the clearest case - every figure is preserved rather than averaged into false precision.
Frequently Asked Questions
What soil pH do collard greens need?
A pH of about 6–6.5. That span reflects genuine variation between the authorities we cite rather than a single agreed figure — the References section lists each source's exact range.
What problems affect collard greens?
Our data links 2 diseases and 4 pests to this crop. See the sections above for each one and how to manage it.
Plan next season before the problems start
Short-season growing is arithmetic before it is technique: days to maturity against frost-free days decides what will finish at all. The Canada Garden Planner does that subtraction for your region before you sow.
Get the Canada Garden Planner →Instant PDF download · Written for Canadian growing conditions
Vegetable Growing Guides Canada
Last verified 2026-08-29
Where To Go From Here
Take this crop from reading into a written plan for your own beds.
Plan the next step
Use the printable SoilCommander planner for your region to turn this guide into sowing dates, bed layouts and weekly garden tasks.