Collard Greens in Zone 3a & 3b
Brassica oleracea (Acephala group)
Yes, collard greens grow in zones 3a and 3b. Start seeds indoors Apr 11–Apr 18 and plant out May 9–May 16.
When to plant collard greens in zone 3b
Zones 3a and 3b share the same average frost dates, so this page covers both.
Method: Either: Start indoors for an earlier harvest, or direct-sow outside for less fuss. Either works.
| Start indoors | Apr 11–Apr 18 |
|---|---|
| Direct sow / transplant outside | May 9–May 16 |
| Estimated harvest | Jul 18–Jul 25 (~70 days after planting) |
Spacing: 1 per square foot (square-foot-gardening spacing). Mature height: 2-3 ft.
Plant alongside it in zone 3b
These go outside within two weeks of collard greens in zone 3b, so one planting day can cover them.
- RadishMay 2–May 9
- CarrotMay 9–May 16
- CabbageMay 16–May 23
- LettuceMay 16–May 23
- BeetMay 9–May 16
- Broccoli Rabe (Raab)May 9–May 16

Collard greens are a Southern staple for a reason: they're tough, cold-hardy, and keep producing edible leaves through conditions that would end most other greens for the season. The tradeoff is that they take space and time. This isn't a quick, tuck-it-anywhere crop.
How collard greens fit zone 3's season
Zone 3b's frost-free window runs about 98 days, from May 30 to September 5. Collard greens need about 70 days from sowing to first harvest.
Collard Greens planting windows in every zone
Zone 3b is highlighted. Useful for comparing against a neighbouring zone, or for a garden somewhere else.
| Zone | Start indoors | Sow or plant out | Harvest |
|---|---|---|---|
| 3a & 3b (your zone) | Apr 11–Apr 18 | May 9–May 16 | Jul 18–Jul 25 |
| 4a & 4b | Mar 27–Apr 3 | Apr 24–May 1 | Jul 3–Jul 10 |
| 5a & 5bSpring window | Mar 22–Mar 29 | Apr 19–Apr 26 | Jun 28–Jul 5 |
| Fall window | Not usually | Jul 13–Jul 27 | Sep 21–Oct 5 |
| 6a & 6bSpring window | Mar 7–Mar 14 | Apr 4–Apr 11 | Jun 13–Jun 20 |
| Fall window | Not usually | Jul 23–Aug 6 | Oct 1–Oct 15 |
| 7a & 7bSpring window | Feb 20–Feb 27 | Mar 20–Mar 27 | May 29–Jun 5 |
| Fall window | Not usually | Aug 2–Aug 16 | Oct 11–Oct 25 |
| 8a & 8bSpring window | Feb 4–Feb 11 | Mar 4–Mar 11 | May 13–May 20 |
| Fall window | Not usually | Aug 18–Sep 1 | Oct 27–Nov 10 |
| 9a & 9bSpring window | Dec 28–Jan 4 | Jan 25–Feb 1 | Apr 5–Apr 12 |
| Fall window | Not usually | Sep 12–Sep 26 | Nov 21–Dec 5 |
| 10a & 10bSpring window | Dec 12–Dec 19 | Jan 9–Jan 16 | Mar 20–Mar 27 |
| Fall window | Not usually | Sep 27–Oct 11 | Dec 6–Dec 20 |
| 11a & 11bFall window | Not usually | Sep–Jan | ~70 days after planting |
Harvest dates are about 70 days after the sow or plant-out date, not after starting seeds indoors.
Good companions
- Onion: Onion scent may help deter common collard pests.
- Dill: Attracts beneficial predatory wasps that help protect brassicas.
Where to buy collard greens seeds
Varieties we recommend, and where to get them:
- Georgia Southern (Creole): NC State Extension identifies Georgia Southern, along with Vates, Carolina Improved Heading (Morris), Blue Max, and Heavi Crop, as varieties that have consistently done well in North Carolina. Buy: Botanical Interests Full notes
See why we recommend these suppliers →
As an Amazon Associate we earn from qualifying purchases. Some links on this page also go to other retailers we may earn a commission from as an affiliate, at no extra cost to you. We only recommend products with a clear consensus of positive, independent reviews, or ones we bought and use ourselves. Each item on our gear page says which.
See it growing
Search YouTube for "growing collard greens" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)
← Back to the full zone 3b calendar · Plan your beds in the Garden Designer →

Pin this for later
Growing Collard Greens in USDA zone 3b: when to start seeds indoors, when to direct-sow, and when to expect a harvest.
Save to Pinterest