Why Aren't My Irises Flowering? - Sunshine Iris Nursery

Why Aren't My Irises Flowering? - Sunshine Iris Nursery

Were you impressed with your irises last Spring?

By now your bearded iris should have given you a truly delightful display, and have started to enter their period of dormancy. If your iris have not flowered well, there could be a number of reasons for this.

Iris need at least half a day of full sun, and will even do well in full sun all day.

Some of the darker flowering varieties may flower better if they are in the shade in the afternoon, but generally they are true Aussie sunbakers and love to languish in the open.

Sunshine Iris Nursery in full flower
Perhaps you may be worried about frost on your fully exposed iris but in actual fact they require frost on the rhizome to encourage blooming as well.  So please don't mulch heavily around your iris, especially in winter.
Another factor which may prevent your iris flowering, is too much fertiliser.  Iris are not big fans of nitrogen, rather preferring potassium and phosphorus.  A fertiliser containing P or K such as Dynamic Lifter or a slow release fertiliser like Osmocote, are best for irises.

Sounds like the perfect plant - full sun, not much mulch, frost hardy, low fertiliser requirements? We think so!!

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