Answer: Ornamental grasses are generally divided as a means of propagation. Your method was correct, but perhaps the timing was poor. Cyperus is a bog sedge, but will grow out of water as well, in rich, moist soil. Division can be made in spring or autumn, replanting the smaller, outside divisions and discarding the old centers. You can also save seeds to sow in the spring. Try again, saving only the newest, smallest stems for replanting, and making sure each division has lots of healthy roots.
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