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When Do Iris Flowers Bloom? How Long Does the Season Last?

purple iris flowers blooming

Irises are beautiful flowers that feature six distinct petals. Many people cherish irises for their looks, but they are also vigorous pollinators. Irises attract bees, butterflies, and other pollinating insects to your garden. That means it is important to know when your iris is going to bloom. Many people feature irises in their butterfly gardens and plan other summer plants around the iris’s ability to attract pollinating insects.

So, when do iris flowers bloom? How long do they bloom? Do irises have a long blooming season or a short one? This guide will answer all of those questions and more so you can become more familiar with your favorite flowers.

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When Iris Flowers Bloom

Purple Iris Bulb
Image By: Etienne-F59, Pixabay

The blooming seasons for irises are spring and summer. There are over 250 different species and varieties of iris plants, and each one blooms at a slightly different time. The earliest varieties will bloom in mid to late spring. The latest irises can start blooming at the tail end of summer. Most varieties fall somewhere in the middle.

The earliest irises start to bloom in the temperate Pacific Northwest. Irises in warm parts of Oregon and Washington have been known to bloom as early as March if the weather is just right. The latest blooming iris varieties bloom in September or October. These plants sneak in their flowers right before the weather takes a turn towards cold. Some irises will bloom twice during this period.

Bloom Season Months
Early March – May
Typical June – August
Late September – October

How Long Each Bloom Lasts

Irises typically bloom for an average of two weeks per season. Some irises can bloom for longer, stretching to three weeks. But the average time an iris is in bloom before the petals start to fall is two weeks. There are some methods online that claim you can stretch your irises’ bloom time from two weeks to four weeks by manipulating the environment and the plant. These methods were not tested here, and we cannot verify their effectiveness or their safety for your iris.

When your iris blooms, count on two solid weeks of flowers before the blooms start to fade and fail. If you are lucky, your plant might eke out an extra week if thriving.

Remontant Irises

orange iris flower
Image Credit: Piqsels

Some irises are labeled as remontant. Remontant is a term for plants that bloom or fruit twice in a single season. Colloquially, these irises are sometimes called reblooming irises. There are a few species of irises that can produce two separate blooms in one season. A remontant iris will typically bloom once early in the season (late spring) and then late in the season (middle to end of summer) for a total of four to six weeks of flowers.

If you really like iris flowers, you should consider finding a reblooming iris and double your flower’s bloom time each year.

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Iris Flower Terminology

When doing research into irises, you will come across a lot of terminology that is unique or rare. Before you get confused, take a look at some phrases you will run into when looking at irises.

Bearded

Bearded Iris
Image Credit: Ralphs_Fotos, Pixabay

Many irises are considered bearded. Bearded irises have fine hairs in the middle of their falls. Hence the term bearded. The hairs appear below the flower where a beard would be on a person’s face.


Crested

Crested Iris
Image By: GabrielDouglas, Pixabay

Crested irises have no hairs on their falls. Crested irises are sometimes called beardless irises. Bearded and crested are the two main types of irises available on the market.


Falls

purple irises
Image Credit: zoosnow, Pixabay

Falls is the term for the petals that point down towards the ground. Irises typically have six petals. Three on the top and three on the bottom.


Standards

Yellow Flag Iris
Image Credit By: xivic, Pixabay

Standards are the petals on the top of the iris. They point upwards, like flags or standards.


Iris germanica

maroon iris germanica close up
Image Credit: Sonja Kalee, Pixabay

Iris germanica is the most common species of the iris that is kept as a house plant. There are hundreds of varieties, but most irises are either Iris germanica or a variety of this species. This species is a bearded iris.

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Conclusion

Next time you are looking for irises, you will know when they should bloom, how long they should bloom for, and some of the common terms that come with buying an iris. Irises are beautiful and complex plants that have a lot to them. Shoot for a good summer bloom and plan your garden around the irises if you are hoping to use the flowers to attract pollinators to your garden space.


Featured Image Credit: マサコ アーント, Pixabay

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