Northern Blue Flag Iris Versicolor

Light Needs

Full Sun

(6+ Hours Direct Sun)

Mature Height

2-3 Feet

Mature Spread

2 Feet

Growing Zones

3 to 8

Flag Iris make a great addition to any damp, boggy area in the garden. Northern Blue Flag Iris sports blue-purple flowers and lovely green sword-like leaves that give structure to a wildlife planting. The white striped landing strip of the sepals helps attract pollinators and other beneficial insects.  Iris versicolor is native to eastern area of North America. Unlike the Yellow Flag Iris, this one is well behaved and worthy of inviting next to your pond.

Wildlife use this native Iris not only for energy from its nectar, but as a sheltered spot to rest or hide in the pond. Flag Iris is also a useful plant to include in Rain Gardens. Depending on the design, Iris versicolor could be planted in the center (zone 1) or on the still boggy and seasonally dry (zone 2) edges. Once established, these lovely blue bloomers are very maintenance and trouble free.

Northern Blue Flag Iris Care

This semi evergreen perennial really likes to have wet feet but a sunny face. The edge of a pond is ideal, but any mostly damp location will work. This Iris is not particular about the soil pH or texture. Heavy clay soil or sandy loam soil is fine because the plant will adapt to many soil conditions. Native plants do not generally need supplemental fertilizing to perform at their best. Dividing Iris versicolor after 2-3 years is the best way to keep it blooming.

Blue Flag Iris blooms from late spring until mid-summer and sets vivid orange berries. These bloom heads can be left on the plant to provide food for birds through the winter. The seeds will easily germinate for propagation. Dividing the rhizomes is another easy way to spread Blue Flag Iris. 

Northern Blue Flag Iris Spacing

Blue Flag Iris looks best when it is planted in a large group. The height is a modest 24-36 inches, while the width of each plant is narrow at 18-24 inches. Spacing each rhizome at 12-18 inches, center on center, will help Flag Iris fill in an area quickly.

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