Cold Hardy Iris Plants – Choosing Irises For Zone 5 Gardens

Close Up Of Iris Plant
zone 5 iris
(Image credit: PurpleImages)

The iris is a mainstay of many gardens. It's beautiful, unmistakable flowers appear in the spring, just as the first spring bulbs are beginning to fade. It’s also an extremely diverse genus of plants, which means you ought to be able to find plenty of irises for your garden, no matter your growing conditions and tastes. Since irises are so diverse, there are plenty of cold hardy iris varieties available. Keep reading to learn more about growing iris plants in cold climates, specifically how to pick the best irises for zone 5.

Growing Irises in Zone 5

There are plenty of cold hardy iris varieties available. In fact, many irises like the cold and prefer having a drop in temperature during which they become dormant. This isn’t the case for all irises, but it is for many. You won’t be able to grow all irises in zone 5, but you are certainly not without options. When growing iris plants in cold climates, their care isn’t much different than anywhere else. While you can lift the rhizomes for storage over winter, hardy irises generally do fine left in the ground, given a good layer of mulch protection until spring.

Best Zone 5 Iris Varieties

Here are a few of the most popular irises for zone 5 gardening: Japanese Iris – Hardy down to zone 5, Japanese iris has very large flowers at 4 to 8 inches (10-20 cm.) across. It prefers moist soil and likes quite a bit of acidity. Yellow Flag – Hardy down to zone 5, yellow flag iris likes very wet soil and produces striking yellow flowers but can become invasive. Dutch Iris – Hardy down to zone 5, Dutch iris prefers well drained soil and is a good choice for rock gardens. Siberian Iris – As the name suggests, Siberian iris is very cold hardy, performing well all the way down to zone 2. Its flowers come in a wide variety of colors.

Liz Baessler
Senior Editor

The only child of a horticulturist and an English teacher, Liz Baessler was destined to become a gardening editor. She has been with Gardening Know how since 2015, and a Senior Editor since 2020. She holds a BA in English from Brandeis University and an MA in English from the University of Geneva, Switzerland. After years of gardening in containers and community garden plots, she finally has a backyard of her own, which she is systematically filling with vegetables and flowers.