One of my most favorite hypertufa planters is one that I have had planted for several years with a tiny miniature dwarf iris. At only about 4 inches tall, they are darling.
I have some coral carpet sedum in the same planter trough, but this year the plants don’t seem to be doing well. Maybe I don’t yet have them in “The Sweet Spot” where they are getting just the right amount of sun and shade?
When I look for a problem, the most important thing I find for irises is that burying them too deeply effects their blooms. So maybe over the years mine have settled into the soil and are now too deep to bloom?
These iris are not identified by me. I think they could be Iris Pumila because of the shape and size of the blade or leaf. And the size of the huge bloom from these tiny plants. See those blades with a lighted outer edge?
Possible Reasons Iris Have Stopped Blooming
Incorrect Planting Depth: Irises should be planted so the tops of the rhizomes are exposed to the sunlight. If they are planted too deep, they may not bloom.
As I mentioned above, this could be a reason why mine aren’t able to bloom this year. They are too deep in the soil. Calls for a transplanting session!
Age of the Iris: Over time, some irises may simply stop blooming as they get older. If your irises are very old, they may no longer be capable of blooming.
Overcrowding: Over time, irises can become crowded as they multiply. This overcrowding can lead to a decrease in blooming. If your irises are crowded, consider dividing them. I don’t feel like mine are too crowded, but perhaps the sedum is too much?
Lack of Nutrients: Irises need well-draining soil rich in nutrients. If your irises are not getting the necessary nutrients, they may fail to bloom. Consider using a balanced fertilizer to ensure your irises have the nutrients they need.
I have some Bulbtone and I will use this when I replant the hypertufa trough with some fresh soil and thin them out a little. Filling up another hypertufa trough or bowl will not be a problem
Insufficient Light: Irises need at least six hours of direct sunlight each day. If your irises are in a location where they do not receive enough sunlight, they may not bloom.
Currently my hypertufa trough full of irises is in full sun all day but afternoons have a shadow cast from the house. Relocation coming up.
Age of the Iris: Over time, some irises may simply stop blooming as they get older. If your irises are very old, they may no longer be capable of blooming. However some gardeners report that they have irises that have thrived for decades with optimum care.
Disease or Pests: If your irises are being attacked by pests or disease, they may not bloom. Inspect your plants, especially in July, for brown leaf tips or dying leaves. Dig up the rhizomes and look for borers or tunnels from boring caterpillars.
Complete Dig Up and Replant of Miniature Iris
There will be a video that goes with this post in case you want to see a version of it live. I will put it here on the post and hopefully that will be a help if you decide to do any revamp of your iris.
Since I am not really sure how many years this iris hypertufa trough has been planted, I decided that the soil needed to be replaced and refreshed with Bio-tone ( I had ran out of Bulbtone) to give the iris energy for blooms next spring.
You can see in the video that the soil looked good and seemed to be well drained, but why not replace it since I am hoping for new results.
I tried cleaning up the iris while I was transplanting and learned some lessons about removing browned leaves. When I tried to yank upwards, I tore the plant. But “peeling” them downwards removed them easily. Which is the best way?
When I transplanted them all, making them as close to the surface as possible, I added a layer of pea gravel across the top. I may remove a bit of it after they have anchored in well.
So how do they look?