- Hardiness
- Zones 5 to 9
- Light
- Full sun
- Water
- Low, drought tolerant once settled
- Size
- 4 to 6 in
- Blooms
- Late winter
- Colors
- blue, purple
- Planting depth
- 4 inches
Growing tip. One of the first flowers of the year. Needs dry summers to come back, so plant in a sunny well-drained spot.
When to plant dwarf iris by zone
| Zone | Median last / first frost | When to plant | Winter |
|---|---|---|---|
| 3b | May 16 / Sep 25 | Plant bulbs: Aug 28 to Oct 16 | Too cold |
| 4a | May 12 / Sep 28 | Plant bulbs: Aug 31 to Oct 19 | Too cold |
| 4b | May 8 / Oct 1 | Plant bulbs: Sep 3 to Oct 22 | Too cold |
| 5a | May 3 / Oct 5 | Plant bulbs: Sep 7 to Oct 26 | Comes back |
| 5b | May 1 / Oct 10 | Plant bulbs: Sep 12 to Oct 31 | Comes back |
| 6a | Apr 29 / Oct 16 | Plant bulbs: Sep 18 to Nov 6 | Comes back |
| 6b | Apr 22 / Oct 22 | Plant bulbs: Sep 24 to Nov 12 | Comes back |
| 7a | Apr 16 / Oct 25 | Plant bulbs: Sep 27 to Nov 15 | Comes back |
| 7b | Apr 5 / Nov 1 | Plant bulbs: Oct 4 to Nov 22 | Comes back |
| 8a | Mar 29 / Nov 7 | Plant bulbs: Oct 10 to Nov 28 | Comes back |
| 8b | Mar 16 / Nov 14 | Plant bulbs: Oct 17 to Dec 5 | Comes back |
| 9a | Mar 2 / Nov 26 | Plant bulbs: Oct 29 to Dec 17 | Comes back |
| 9b | Feb 1 / Dec 9 | Plant bulbs: Nov 11 to Dec 30 | Comes back |
Zones 10 and warmer have little or no frost. There, plant cool-season plants in fall and warm-season plants from late winter.
Similar bulbs
TulipFull sun · Zones 3 to 7
Ornamental onionFull sun · Zones 4 to 8
Asiatic lilyFull sun · Zones 3 to 9
DahliaFull sun · Zones 8 to 11
GladiolusFull sun · Zones 8 to 11
CannaFull sun · Zones 8 to 11More for your zone: zone 5 bulbs, zone 6 bulbs, zone 7 bulbs, zone 8 bulbs, zone 9 bulbs.
Frequently asked questions
What zone does dwarf iris grow in?
Dwarf iris is hardy in USDA zones 5 to 9. Outside that range it struggles with the winter. Find your zone by ZIP code.
How much sun does dwarf iris need?
Full sun. Full sun means at least six hours of direct sun a day; part shade means about three to six.
Hardiness ranges, light and size are typical figures from university extension services and botanic garden plant records; a named variety can differ, so check its tag. Planting dates come from each zone's median frost dates (NOAA 1991 to 2020 climate normals) and the timing rules in how we check.