Calendula in Zone 9a & 9b
Calendula officinalis
Yes, calendula grows in zones 9a and 9b. Start seeds indoors Dec 28–Jan 4 and plant out Feb 1–Feb 8.
When to plant calendula in zone 9b
Zones 9a and 9b 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 | Dec 28–Jan 4 |
|---|---|
| Direct sow / transplant outside | Feb 1–Feb 8 |
| Estimated bloom | Mar 23–Mar 30 (~50 days after planting) |
Spacing: 1 per square foot (square-foot-gardening spacing). Mature height: 1-2 ft.
Plant alongside it in zone 9b
These go outside within two weeks of calendula in zone 9b, so one planting day can cover them.
- Agrostemma (Corn Cockle)Feb 1–Feb 8
- AstilbeFeb 1–Feb 8
- Bachelor's Button (Cornflower)Feb 1–Feb 8
- Bupleurum (Thoroughwax)Feb 1–Feb 8
- California PoppyFeb 1–Feb 8
- CandytuftFeb 1–Feb 8
Calendula is one of the earliest things you can get in the ground. It tolerates a light frost and is often started before most of the garden is even planted, and it earns its keep once established, commonly reported to draw in the predatory insects that prey on tomato hornworms. What you get for the trouble is a low, 12- to 18-inch mound covered in simple daisy-like blooms in orange or yellow.
How calendula fits zone 9's season
Zone 9b's frost-free window runs about 293 days, from February 15 to December 5. Calendula needs about 50 days from sowing to first bloom.
Calendula planting windows in every zone
Zone 9b is highlighted. Useful for comparing against a neighbouring zone, or for a garden somewhere else.
| Zone | Start indoors | Sow or plant out | Bloom |
|---|---|---|---|
| 2a & 2b | Apr 1–Apr 8 | May 6–May 13 | Jun 25–Jul 2 |
| 3a & 3b | Apr 11–Apr 18 | May 16–May 23 | Jul 5–Jul 12 |
| 4a & 4b | Mar 27–Apr 3 | May 1–May 8 | Jun 20–Jun 27 |
| 5a & 5b | Mar 22–Mar 29 | Apr 26–May 3 | Jun 15–Jun 22 |
| 6a & 6b | Mar 7–Mar 14 | Apr 11–Apr 18 | May 31–Jun 7 |
| 7a & 7b | Feb 20–Feb 27 | Mar 27–Apr 3 | May 16–May 23 |
| 8a & 8b | Feb 4–Feb 11 | Mar 11–Mar 18 | Apr 30–May 7 |
| 9a & 9b (your zone) | Dec 28–Jan 4 | Feb 1–Feb 8 | Mar 23–Mar 30 |
| 10a & 10bFall window | Aug–Sep | Sep–Nov | ~50 days after transplanting |
| 11a & 11b | Nov 13–Nov 20 | Dec 18–Dec 25 | Feb 6–Feb 13 |
Bloom dates are about 50 days after the sow or plant-out date, not after starting seeds indoors.
Zone 2 sows before zone 3 here, which looks wrong and is not. USDA zones rank winter cold, not season length, and zone 2 is mostly interior Alaska, where hard winters come with warm summers. More on what a zone measures.
Good companions
- Tomato: Penn State Extension confirms calendula attracts beneficial insects that prey on aphids: the more specific claim that it targets hornworm predators isn't what that research shows, so treat calendula as a general aphid-predator draw near tomatoes rather than a hornworm-specific one.
Where to buy calendula seeds
Botanical Interests · True Leaf Market · Burpee · High Mowing Organic Seeds (each supplier's calendula seeds)
Varieties we recommend, and where to get them:
- 'Pacific Beauty': Utah State University Extension notes this variety, along with 'Coronet', has increased heat tolerance compared to other calendula, useful if your garden runs warmer than calendula's preferred cool-season range. Buy: Botanical Interests · True Leaf Market · High Mowing Organic Seeds Full notes
- 'Resina': Utah State University Extension notes this variety has high resin content in the blooms, the pick specifically if you're growing calendula for its traditional medicinal/skin-care use rather than as a cutting or bedding flower. Buy: Botanical Interests · High Mowing Organic Seeds 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 calendula" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)
← Back to the full zone 9b calendar · Plan your beds in the Garden Designer →
Pin this for later
Growing Calendula in USDA zone 9b: when to start seeds indoors, when to direct-sow, and when to expect a bloom.
Save to Pinterest