Xeranthemum (Immortelle) in Zone 9a & 9b
Xeranthemum annuum
Yes, xeranthemum (immortelle) grows in zones 9a and 9b. Start seeds indoors Jan 4–Jan 11 and plant out Feb 15–Feb 22.
When to plant xeranthemum (immortelle) 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 | Jan 4–Jan 11 |
|---|---|
| Direct sow / transplant outside | Feb 15–Feb 22 |
| Estimated bloom | May 11–May 18 (~85 days after planting) |
Spacing: 4 per square foot (square-foot-gardening spacing). Mature height: 1.5-2 ft.
Plant alongside it in zone 9b
These go outside within two weeks of xeranthemum (immortelle) in zone 9b, so one planting day can cover them.
- NasturtiumFeb 22–Mar 1
- MarigoldFeb 22–Mar 1
- African DaisyFeb 15–Feb 22
- Amaranthus (Love-Lies-Bleeding)Feb 15–Feb 22
- Ammi (False Queen Anne's Lace)Feb 15–Feb 22
- Ammobium (Winged Everlasting)Feb 15–Feb 22

Xeranthemum, also called immortelle or paper flower, is a papery-petaled daisy relative that holds its color remarkably well once dried, which is the entire reason it's grown.
How xeranthemum (immortelle) fits zone 9's season
Zone 9b's frost-free window runs about 293 days, from February 15 to December 5. Xeranthemum (immortelle) needs about 85 days from sowing to first bloom.
Xeranthemum (Immortelle) 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 8–Apr 15 | May 20–May 27 | Aug 13–Aug 20 |
| 3a & 3b | Apr 18–Apr 25 | May 30–Jun 6 | Aug 23–Aug 30 |
| 4a & 4b | Apr 3–Apr 10 | May 15–May 22 | Aug 8–Aug 15 |
| 5a & 5b | Mar 29–Apr 5 | May 10–May 17 | Aug 3–Aug 10 |
| 6a & 6b | Mar 14–Mar 21 | Apr 25–May 2 | Jul 19–Jul 26 |
| 7a & 7b | Feb 27–Mar 6 | Apr 10–Apr 17 | Jul 4–Jul 11 |
| 8a & 8b | Feb 11–Feb 18 | Mar 25–Apr 1 | Jun 18–Jun 25 |
| 9a & 9b (your zone) | Jan 4–Jan 11 | Feb 15–Feb 22 | May 11–May 18 |
| 10a & 10b | Dec 19–Dec 26 | Jan 30–Feb 6 | Apr 25–May 2 |
| 11a & 11b | Nov 20–Nov 27 | Jan 1–Jan 8 | Mar 27–Apr 3 |
Bloom dates are about 85 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
No well-established companions for xeranthemum (immortelle).
Where to buy xeranthemum seeds
None of the seed suppliers we list carries xeranthemum seeds right now. A local garden center or a specialty seed house is the place to look.
See why we recommend these suppliers →
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See it growing
Search YouTube for "growing xeranthemum (immortelle)" 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 →

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Growing Xeranthemum (Immortelle) in USDA zone 9b: when to start seeds indoors, when to direct-sow, and when to expect a bloom.
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