Among them were rue, Italian catnip, savory, sage, soapwort, cyperus, white and black hellebore, and pennyroyal.
From the en.wikipedia.org
This is a Sibudu cyperus sp.
From the sciencedaily.com
Cyperus are African natives and fast-growing members of the sedge family but not hardy to frosts so there is no danger of them taking over your pond or water fall.
From the thenewstribune.com
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Type genus of Cyperaceae; grasslike rhizomatous herbs; cosmopolitan except very cold regions
Cyperus is a large genus of about 600 species of sedges, distributed throughout all continents in both tropical and temperate regions. They are annual or perennial plants, mostly aquatic and growing in still or slow-moving water up to 0.5 m deep. ...
Cf. LIGULARIS L. Ceda (Cu); Purua (C). The aromatic roots are used by the Cuna for debility and stomachache.