When to Plant Sunflowers
Sow sunflowers outside from your last frost to 4 weeks after it.
Sunflowers at a glance
- Sow outside
- from your last frost to 4 weeks after it
- Time to bloom
- 70 to 100 days from sowing
- In bloom for
- about 6 weeks
- Spacing
- 1 plant per square foot
- Frost
- Tender: frost kills it
Growing sunflowers
Sunflowers are easy to sow straight in the garden in full sun, about an inch deep. Tall single-stem kinds make one big head; branching kinds give many smaller flowers for cutting over a long season.
Dates by hardiness zone
Typical dates for each zone; your ZIP code gives your own.
| Zone | Sow | In bloom |
|---|---|---|
| Zone 3a | May 28 – Jun 25 | Aug 6 – Sep 14Pick a fast variety. |
| Zone 3b | May 17 – Jun 14 | Jul 26 – Sep 22 |
| Zone 4a | May 12 – Jun 9 | Jul 21 – Sep 17 |
| Zone 4b | May 8 – Jun 5 | Jul 17 – Sep 13 |
| Zone 5a | May 3–31 | Jul 12 – Sep 8 |
| Zone 5b | May 1–29 | Jul 10 – Sep 6 |
| Zone 6a | Apr 29 – May 27 | Jul 8 – Sep 4 |
| Zone 6b | Apr 23 – May 21 | Jul 2 – Aug 29 |
| Zone 7a | Apr 16 – May 14 | Jun 25 – Aug 22 |
| Zone 7b | Apr 5 – May 3 | Jun 14 – Aug 11 |
| Zone 8a | Mar 29 – Apr 26 | Jun 7 – Aug 4 |
| Zone 8b | Mar 17 – Apr 14 | May 26 – Jul 23 |
| Zone 9a | Mar 2–30 | May 11 – Jul 8 |
| Zone 9b | Feb 15 – Mar 15Nights are still cool before mid-February, so this starts a little later. | Apr 26 – Jun 23 |
| Zone 10a | Feb 15 – Mar 15 | Apr 26 – Jun 23 |
| Zones 10b–11b | Frost is rare here, so sunflowers can go in from late winter, and again in late summer for a fall crop. | |
Questions about sunflowers
Can I grow sunflowers in pots?
Dwarf varieties do well in pots in full sun. Tall kinds need open ground to anchor their roots.
How do I save sunflower seeds?
When the back of the head turns brown and the seeds are plump, cut the head with some stem and hang it somewhere dry and airy, covered with a paper bag.
