Zantedeschia

A bold, clumping rhizomatous perennial grown for its elegant, pure-white funnel-shaped flowers — actually a curved spathe wrapped around a yellow finger-like spadix — held on tall stems above large, glossy, arrow-shaped deep-green leaves from late winter into summer. Native to the wetlands and seeps of southern Africa, Zantedeschia aethiopica is the classic florist's calla and a striking water-margin and container plant, thriving in consistently moist to wet rich soil in full sun to part shade. It is tender (hardy in zones 8a-10b), where it overwinters in the ground and can be near-evergreen; colder gardeners grow it from lifted rhizomes or under heavy mulch. Two cautions are load-bearing: every part is toxic if eaten (calcium-oxalate raphides), and in mild, wet climates it can escape and naturalize into an invasive weed.

Golden calla is a tuberous perennial in the arum family (Araceae) grown for its large, brilliant golden-yellow funnel-shaped spathes — typically marked with a deep purple blotch at the base and wrapping a matching yellow spadix — held on stout stems above deep-green, white-spotted leaves in summer. Its wild origin is genuinely uncertain: it is said to occur in Mpumalanga province (former Transvaal), South Africa, but credible sources treat it as a garden plant of unknown parentage with no confirmed wild population (Wikipedia). In the garden it is a bold container and border accent for zones 8-10, and it overwinters as a lifted tuber in colder climates. The honest catch is threefold: every part is toxic (calcium-oxalate raphides cause intense oral burning — hazardous to children, pets, and livestock), the plant is frost-tender (RHS H1C) and must be lifted and stored dry below about zone 9, and it dislikes sitting in wet soil during dormancy — distinctly more drought-tolerant but more rot-prone than its white-spathed cousin Z. aethiopica.