How to Make a Water Iris Bloom
- 1). Compost water iris plants each spring. When composting, always leave the rhizome exposed, with a thin layer of compost surrounding it.
- 2). Add fertilizer when you compost your plants. Use iris-specific fertilizer and always follow manufacturer directions.
- 3). Prune flower stalks after the flowers have faded. This will encourage reblooming and keep your plant clean and neat.
- 4). Prune the plant again in the autumn. Get rid of dead leaves and stems. Trim the healthy leaves back to within 4 to 5 inches of the main stalk.
- 5). Cover rhizomes with a healthy layer of mulch before the winter to protect them from the cold.
- 6). Divide iris plants and rhizomes every 5 years or so, or when you notice restricted blooming. This will keep the plants healthy and controlled.
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