Answer: If your African Iris has been in the ground for 8 years, it's probably time to dig them all, cut away the dead foliage, divide the clumps, and replant them in the bed. As you're doing this you can remove the weeds in the flower beds. Replant the African iris, then place a 3-4" organic mulch over the entire bed to help suppress weeds.
Best wishes with your garden!
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