Answer: Because your African irises are in clay pots, the safest way to feed without over-feeding is to use a water soluable fertilizer such as Miracle Gro, Peter's, or Shultz's. Use a half-strength dilution and apply every 3-4 weeks during the growing season. I'll bet your plants have stopped blooming because they are rootbound. Overcrowded roots will slow or even stop irises from blooming. You might want to unpot them and see how the root systems are doing. If all you find are masses of roots and not much potting soil, it's time to divide and repot them. Use fresh potting soil in each pot and be sure to water thoroughly after they been repotted. They should bloom for you next year. Enjoy!
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