Iris prismatica: complete guide

Overview

Iris prismatica, commonly called slender blue iris or slender blue flag, grows naturally in Eastern America in wetland habitats.

Appearance

The plant is elegant with narrow upright foliage and characteristic blue to lavender flowers in spring.

Ideal Location

This iris grows best in full sun to partial shade in locations where water is regularly present.

Soil

The plant requires moist to wet soil, typical of wetland habitats.

Watering

Watering is fundamental. Ensure soil remains continuously moist.

Pruning

Minimal pruning needed. Remove spent flowers after blooming.

Maintenance Calendar

Spring: Check soil moisture. Summer: Supply regular water. Autumn: Maintain moisture. Winter: Minimize watering.

Winter Hardiness

Hardy to zone 4.

Companion Plants

• Iris versicolor (Dwarf blue flag)
• Sagittaria latifolia (Arrowhead)
• Pontederia cordata (Pickerel rush)
• Eupatorium (Joe-Pye weed)
• Asclepias incarnata (Swamp milkweed)

Find these plants at specialty water garden nurseries.

Closing Thoughts

This beautiful American iris makes a valuable addition to moist garden zones with its blue spring flowers.