When do you cut back irises? Expert advice for the the best blooms

Discover when you should cut back irises – and why it is so important for your garden

Close up of a large group of purple iris flowers in a feild
(Image credit: Alamy)

With over 250 species of iris around the world, these tall, colorful plants, are desirable pops of color in many gardens. Luckily, despite their numerous varieties, many share the same appearance and gardening needs. As the cooler months approach, learn when to cut back irises to protect their beautiful blooms the following year. 

Irises make wonderful additions to any garden ideas, and their delicate blooms and soft colors stand out beautifully in cottage garden ideas. Once you have taken the time to learn how to grow irises, cutting back irises should be done annually to ensure your plant remains healthy through the winter in preparation for the following spring. 

Here, gardening expert Rachel Crow, garden editor for Homes & Gardens, has shared her tips on when to cut back irises, as well as why it is crucial to prolonging your plants. 

rachel crow
Rachel Crow

Rachel has written for lifestyle magazines for many years, with a particular focus on gardening. 

Now focusing on gardening content on Homes and Gardens and its sister brands, she finds every day is a journey of discovery, whether it is learning about new plants or gardening techniques, or sharing the advice of passionate horticultural experts and garden designers. 

When do you cut back irises?

Close up of a white iris flower

(Image credit: Alamy)

'Irises typically die away as the temperatures get cooler, so it is a good idea to start pruning and cutting back your iris plants in fall,' explains Rachel. 'You should begin cutting irises back after flowering and the blooms have all begun to fade. The remainder of the plant's foliage should be left until the first signs of frost, however.' Deadheading irises throughout the blooming season in spring and summer should be avoided, unlike deadheading pansies, as these plants only bloom once. 'Cutting back iris flowers helps keep the plant looking tidy, rather than help restore energy for new flowers,' Rachel continues. 

It is worth noting that if you intend to split irises, it should be done after the plants have flowered, but before cutting back for winter.

'Allowing the leaves to die back naturally in fall before winter frosts allows the plant to gather and restore its energy in preparation for the following spring,' she adds. 'Cut away any remaining leaves and stem to just above the soil line in mid-fall. Cutting the leaves and stems back before this may risk weaker or non-flowering plants the next year.' 

Why should you cut back irises?

Close up of a large group of purple iris flowers in a feild

(Image credit: Alamy)

As with many other plants, there are a few reasons why you should cut back your irises such as protecting the roots and allowing the plant to regain its energy. The most important reason, however, is to prevent overwinter diseases. 

'Irises, particularly bearded irises, are prone to several diseases such as blight, leaf spot, and soft rot,' explains Rachel. 'These diseases can quickly kill a plant so cutting back infected parts as soon as possible can help maintain the rest of the plant. Pruning at the end of each season can also help to prevent diseases from setting in over damp winters.' 

How to cut back irises  

Close up of a yellow iris flower

(Image credit: Alamy)

To cut back irises, start by removing the dead flower heads once they have faded and begun to shrivel. This can be done as soon as they start to die off around late spring and early summer. 

'When cutting back the iris plant, use sharp, clean pruning shears and trim the stem so that only three inches remain out of the soil,' recommends Rachel. 'Try to make crisp cuts with no tears to ensure healthy plants next year.' Make sure to dispose of any leaves in your compost, removing any diseased leaves to your regular waste bin if needed. 

'When cutting back your irises, take the time to check for any pests and disease in the plant and surrounding soil,' Rachel suggests. 

Can you cut back iris leaves after they bloom?

While you can cut back iris leaves and stems after they have bloomed, it is recommended to leave the foliage on the plant until mid-fall to allow the plant to regain its energy to survive the winter and rebloom the following year. 

What do you do with iris seed pods? 

Iris seed pods can be used to grow more iris plants as long as they are stored correctly after harvesting. Learning how to collect and store seeds from your garden plants is an excellent way to populate your garden with your favorite bright blooms affordably.

 Snip Iris seed pods off of the plant in late summer, being careful to not lose any of the seeds as you do so. Store the pods in a cool, dark place until you are ready to use them. 

If you do not want to replant your iris seeds, these pods can be disposed of in your compost or waste bins.