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Iris à crête nain

Iris à crête nain

Iris cristata
Un iris forestier natif de petite taille formant des tapis étalés de feuillage bas en forme d'épée, couronnés brièvement au printemps de délicates fleurs bleu clair ornées de saillants « crêtes » jaunes et blanches sur chaque sépale. L'une des vivaces indigènes les plus charmantes pour les sites à mi-ombre. Parmi les plus petits iris indigènes (15-23 cm de haut) — s'utilise magnifiquement comme couvre-sol sous les arbustes caducs et le long des bordures de sentiers. TOUTES les parties sont toxiques (mise en garde habituelle pour les iris).
Native: 16 US states
Climate fit: broad (74/100)
Filler
Border
Light
Part shade
Water
Moderate water
Mature size
4-9" tall · 12" apart
Hardy in zones
3a-8b
brutally cold to frosty winters
AHS heat range
1-11
Plant range authored in AHS heat-zone terms.
Native in Illinois
No
Native across 16 US states and Canadian provinces — a wide-ranging part of North America's plant communities.

Cold hardiness

Future
These values are location-based: this location's current hardiness is the baseline, and the 2050 value is a projected future climate for this same location.
Now
Zone 6b
USDA
Published baseline for this location from 1991-2020.
Source: USDA Plant Hardiness Zone Map 2023 (1991-2020 climatology) via ArcGIS FeatureServer
Well-suited
2050
Zone 7a
Plotwright
Projected zone for this same location in 2050 (2041-2070) using SSP3-7.0 (regional rivalry).
Well-suited
In plain terms: This location is in Zone 6b today. Its hardiness profile is cold winters, and coldest nights are typically around -3°F. By 2050, the projected hardiness zone is Zone 7a based on SSP3-7.0 (regional rivalry). That is a +0.5-zone shift from Zone 6b to Zone 7a by 2050.
Well-suited today and still thriving in 2050.

Heat tolerance

Future
Heat tolerance values are location-based too: heat days today are observed at this site, and the 2050 value projects this same location under a future climate.
Loading AHS heat-zone data for this location...

Sources & citations

Cite this page
For lesson plans, articles, or research that uses this page. To cite a single upstream fact instead, use its specific source listed below.
Plotwright. (2026, May 17). Iris à crête nain (Iris cristata). Retrieved 2026, June 14, from https://plotwright.garden/plants/iris-cristata
Sources for every fact
Every fact on this page traces to a source. 18 fields cited - 18 source-backed.
NC State Extension Gardener Plant Toolbox
University extension service
Backs 17 fields
Identity
Summary
Plant type
Light
Moisture
Hardiness
Heat zone
Size
Spacing
Habit
Design roles
Seasonal interest
Growth stages
Lifecycle
Regional guidance
Success tips
Designer notes
Wikimedia Commons
Photo · CC BY-SA 4.0
Backs 1 field
Image