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.