Why won’t my Bearded Iris flower?
This can be caused by a number of factors and usually a combination of more than one. For example, planting in too much shade. Overfeeding with animal manure or blood and bone, or the reverse, no feeding of anything. Planting too deep can be a problem. Cover only with 1 to 3 cms of soil. Planting so high that the rhizomes are exposed to extreme sun and wind blowing them around . Don’t mulch the irises, mulching with lawn clippings or other organic matter acts as shade and can cause them to rot. A soil mulch is sufficient. Over or under watering can also cause problems. They need replanting every 3 to 4 years or overcrowded starved Iris will not flower.
When is the best time to replant Iris?
Best time is immediately after flowering, generally late October or November through till the end of January. They can be moved later but next season’s flowering can be disrupted the later you plant them. If you have to move your Iris at another time, it is okay to do this but depending on how late it is, they may not flower until the following year. We have irises flower being replanted as late as March to early April but any time after this, they are unlikely to flower the next Spring but should be fine the following year.
My Iris have changed colour or all gone white
Iris cannot change colour. Usually what occurs is they grow into one another and get mixed then the wrong plant is replanted. If you use weed killers such as Roundup near Iris, it can affect plants and cause flowers to go whiteish and contort. If they recover, the colour will return. If the soil is depleted of nutrients then the flowers may become a paler version of themselves. This will improve once they are replanted and/or fertilized.
How long can Iris stay out of the ground?
Ideally they should be planted immediately on lifting, but can be left in a cool dry place for several weeks. Keep the rhizomes DRY, not moist, as they will rot.
Should I cut the leaves back after flowering?
The foliage should only be cut back when digging and replanting the Iris. Old brown leaves can be removed to tidy up the plant but cutting back the foliage each year can cause less flowering the following season.