Answer: It sounds as though the bed may be overcrowded. Plants that have to compete with one another for moisture and nutrients don't perform as well as those that have a little elbow (and root) room. The flowering stems of fortnight lily are perennial, so don't cut them back after flowering as you might for most other iris like plants. Divide the rhizomatous clumps after the plants have finished flowering (now would be a good time). The new divisions may take several weeks to get established, so be patient and pamper them for a while. They will grow new flower stems as soon as they're established in their new homes.
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