perennial
Douglas iris
Iris douglasiana
Preview: plant data is awaiting horticulturist review. A professional horticulturist hasn't reviewed our plant table yet. Lists still follow fixed rules for zone, sun, pets, deer and invasive status.
Douglas iris is an evergreen perennial hardy in zones 7–10. Expect 1–2 ft of height and 1.5–2 ft of spread; our lists space it 1.5 ft apart. It does best in full sun to part shade with little water once established. Expect purple flowers in March to May. In a FloraVista list it usually plays the filler role: a flowering plant that fills the middle or front of the bed. It is native to California and the Pacific Northwest. Deer usually leave it alone, and it is toxic to dogs and cats. Our rules leave it out of lists in the Southeast, Florida and the Gulf, Texas and the South-Central states and the Desert Southwest, where summer heat, humidity or mild winters hold it back even inside its zone range.
Facts from our plant table
- Botanical name
- Iris douglasiana
- Plant type
- Perennial, evergreen
- Hardiness zones
- 7 to 10
- Sun
- Full sun (6+ hours); Part sun (4–6 hours); Part shade (2–4 hours)
- Water
- Low
- Soil
- Well-drained soil; acid to neutral.
- Mature size
- 1–2 ft tall × 1.5–2 ft wide
- Spacing
- 1.5 ft apart (centre to centre)
- Growth rate
- Medium
- Bloom
- Mar–May · purple
- Roles in a bed
- Filler
- Styles
- natural, low water
- Deer resistance
- High: deer rarely eat it
- Pets
- Toxic to dogs and cats. ASPCA lists iris as toxic (rhizomes): vomiting, drooling.
- Native to
- California and Pacific Northwest
- Pot size and price
- 1-gallon pot, typically $12–$20 (sometimes stocked)
- Plant in
- Fall
- First-year watering
- Water every 1–2 weeks the first dry season; afterwards occasional summer water only.
- Pruning
- Remove old leaves in late summer.
Sources: ASPCA Toxic and Non-Toxic Plant List (from general knowledge; not re-checked unless verification is web-checked); Missouri Botanical Garden Plant Finder and grower tags; State extension service guidance and USDA PLANTS distribution maps; Rutgers NJAES Landscape Plants Rated by Deer Resistance; Invasive Plant Atlas of the United States and state noxious weed lists; Typical 2026 US garden-centre and big-box retail listings (estimate). Not yet reviewed by a horticulturist.
Good companions
The plants our list engine most often puts in the same bed as Douglas iris, across the sun, zone, pet, deer and style combinations it fits.
- Tufted hair grassDeschampsia cespitosaornamental grass · zones 4–9
- Western sword fernPolystichum munitumfern · zones 5–9
- Common yarrowAchillea millefoliumperennial · zones 3–9
- Pennsylvania sedgeCarex pensylvanicaornamental grass · zones 3–8
- Oregon grape 'Compacta'Mahonia aquifolium 'Compacta'shrub · zones 5–9
- Arrowwood viburnum 'Blue Muffin'Viburnum dentatum 'Christom'shrub · zones 3–8
If you can't find it
Substitutes our engine offers for Douglas iris: same role in the bed, passing the same rules.
- Foxglove beardtongue 'Husker Red'Penstemon digitalis 'Husker Red'zones 3–8 · not flagged toxic to pets
- Butterfly weedAsclepias tuberosazones 3–9 · flagged toxic to pets
- Island alum rootHeuchera maximazones 8–10 · not flagged toxic to pets
- Hummingbird sageSalvia spathaceazones 8–10 · not flagged toxic to pets
How this page was made
This page was generated from this plant's record in FloraVista's plant table by fixed rules. The companions and substitutes come from the lists our rules engine composes. No named expert has reviewed this page.
Data status: the plant table is awaiting review by a horticulturist. Check each plant with a local nursery or extension office before you buy.
Sources
- Missouri Botanical Garden Plant Finder, state extension services and the USDA PLANTS database (zones, size, sun, water, bloom, native range)
- ASPCA toxic and non-toxic plant lists (dog and cat toxicity)
- Rutgers NJAES and regional extension deer-resistance ratings
- State noxious-weed and invasive-plant lists and the Invasive Plant Atlas of the US
- Typical US garden-centre listings (pot size and price band)
Generated . How FloraVista chooses plants