With few exceptions, common calla, Zantedeschia aethiopica, blooms exclusively white. ‘Green Goddess’ blooms with green stripes on bigger and more open blooms. ‘Pink Mist’ blooms with a pale pink blush at the bases of its blooms. More colorful summer calla are Zantedeschia elliotiana, which is a different species. Cultivars of common calla are rare.

Calla is an herbaceous perennial that grows from thick rhizomes. It can be invasive, and difficult to eradicate once it gets established. Its basal leaves stand two or three feet high or a bit higher if shaded. More than the lower half of their height is petiole. The upper leaf portion is broad and arrow shaped. All growth is rather spongy and soft, and tears easily.

Callas bloom mostly sporadically for spring, summer and autumn. Mature colonies often bloom with more profuse phases. New rhizomes do not bloom for a few months, though. Individual blooms consist of a solitary flaring spathe surrounding a spike shaped spadix. Compressed flowers adhere tightly to the yellow spadix. Callas are splendid cut flowers.