Since the eggs overwinter on the foliage, it’s critical that you cut back irises in the fall. Throw the leaves back to the rhizomes or bury them if you want to. If you find a soft, rotten rhizome, dig it out and put it in a plastic bag. If you find an iris that has fallen off, you’ll need to remove it from the plant.
You can do this by cutting it off with a pair of scissors, or you can use a sharp knife to cut off a section at a time. Once you’ve removed the entire section, put the whole thing back into the pot and leave it alone for a few days. This will allow the roots to regrow.
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When can I cut off iris leaves?
The best time to cut back on the iris plants is in the fall. After the plants bloom, the foliage should be left on the plant for a few more weeks, since flower stalks can be removed in the spring.
What to do with Siberian iris after flowering?
Remove spent flowers after they bloom to keep seed heads from forming. After the ground has frozen, cut foliage to the ground and mulch it. When large clumps form, divide them to ensure continued growth.
Should irises be cut back for the winter?
It can take several weeks for iris leaves to die back. According to the Utah State University Cooperative Extension, the leaves are usually ready to be cut back by early fall. It is best to cut the leaves back to about 6 to 8 inches above the ground. Wait until after the first frost of the following spring to cut them back again.
Can you cut back iris in the spring?
As soon as they die off around late spring and early summer, this can be done. Rachel recommends cutting back the iris plant with clean shears and trims the stem so that it stays out of the soil. To ensure healthy plants, try to make crisp cuts with no tears.
Why are my iris leaves falling over?
If this has not been done within the past three years, it is time to divide the clump. If they are growing in too much shade or if they have been over-fertilized with a high-nitrogen mix, they will fall over.
Sprouting is a sign that the plant is ready to split, but it can take up to a year for the split to occur. If you are unsure if your plant has split or not, it is best to call your local nursery and ask them to check it out for you.
Should Siberian iris be deadheaded?
Throughout bloom season, most Siberians will remain attractive without regular deadheading. It is a good idea to remove spent bloom stalks, both for garden appearance and to prevent reseeding. After it turns brown and withers in the late summer or early fall, cut back the foliage.
In the spring and early summer, Siberian plants should be fertilized with a mixture of 1/4 to 1 teaspoon per 1,000 sq. ft. of surface area. This fertilizer should not be applied more than once or twice a year. If the soil is not well-drained, the fertilizer may not penetrate deeply enough to be effective.
In areas with poor drainage, fertilization may be necessary in the fall and winter.
Do I need to cover irises during a freeze?
As the temperatures drop below freezing, you can mound a winter protection around your Irises. We recommend evergreen branches or straw. When the weather warms again in the spring, it’s a good time to remove winter protection.