Oregano in Zone 4a & 4b
Origanum vulgare
Yes, oregano grows in zones 4a and 4b. Start seeds indoors Mar 20–Mar 27 and plant out May 22–May 29.
When to plant oregano in zone 4b
Zones 4a and 4b share the same average frost dates, so this page covers both.
Method: Start indoors: Start indoors from seed, then transplant outside. It needs a head start most zones can't give it by direct-sowing alone.
| Start indoors | Mar 20–Mar 27 |
|---|---|
| Direct sow / transplant outside | May 22–May 29 |
| Estimated harvest | Aug 10–Aug 17 (~80 days after transplanting) |
Spacing: 4 per square foot (square-foot-gardening spacing). Mature height: 1-1.5 ft.
Plant alongside it in zone 4b
These go outside within two weeks of oregano in zone 4b, so one planting day can cover them.
- BasilMay 29–Jun 5
- BorageMay 15–May 22
- RosemaryMay 29–Jun 5
- DillMay 8–May 15
- CatmintMay 22–May 29
- Citronella Plant (Mosquito Plant)May 22–May 29
Oregano is a low, spreading perennial in the mint family, and one of the more forgiving herbs you can grow. It performs better in lean, dry soil than in rich, well-watered beds.
How oregano fits zone 4's season
Zone 4b's frost-free window runs about 128 days, from May 15 to September 20. Oregano needs about 80 days from transplant to first harvest.
Oregano planting windows in every zone
Zone 4b is highlighted. Useful for comparing against a neighbouring zone, or for a garden somewhere else.
| Zone | Start indoors | Sow or plant out | Harvest |
|---|---|---|---|
| 4a & 4b (your zone) | Mar 20–Mar 27 | May 22–May 29 | Aug 10–Aug 17 |
| 5a & 5b | Mar 15–Mar 22 | May 17–May 24 | Aug 5–Aug 12 |
| 6a & 6b | Feb 28–Mar 7 | May 2–May 9 | Jul 21–Jul 28 |
| 7a & 7b | Feb 13–Feb 20 | Apr 17–Apr 24 | Jul 6–Jul 13 |
| 8a & 8b | Jan 28–Feb 4 | Apr 1–Apr 8 | Jun 20–Jun 27 |
| 9a & 9b | Dec 21–Dec 28 | Feb 22–Mar 1 | May 13–May 20 |
| 10a & 10bSpring window | Not usually | Feb–Apr | ~80 days after transplanting |
| Fall window | Not usually | Oct–Nov | ~80 days after transplanting |
| 11a & 11b | Nov 6–Nov 13 | Jan 8–Jan 15 | Mar 29–Apr 5 |
Harvest dates are about 80 days after the sow or plant-out date, not after starting seeds indoors.
Good companions
- Bell Pepper: Low, spreading habit fills gaps without competing for light.
Where to buy oregano seeds
Botanical Interests · True Leaf Market · Burpee · High Mowing Organic Seeds (each supplier's oregano seeds)
Varieties we recommend, and where to get them:
- Greek Oregano: Illinois Extension states plainly that if you want to plant "true" oregano, Greek oregano is the one to plant. Buy: Botanical Interests · True Leaf Market · Burpee · High Mowing Organic Seeds Full notes
See why we recommend these suppliers →
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See it growing
Search YouTube for "growing oregano" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)
← Back to the full zone 4b calendar · Plan your beds in the Garden Designer →
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Growing Oregano in USDA zone 4b: when to start seeds indoors, when to direct-sow, and when to expect a harvest.
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