And for the most part, we grow the hybrid cultivars and not one of the six species in cultivation.
This calla lily is not particularly hardy. The crowns die somewhere around 25F (-4C). They tolerate a light frost in the fall but will not overwinter outdoors if you get 25F as a winter temperature.
Plant them so the rhizome base is 3-4 inches deep and 12-inches between plants.
You can grow this plant as a houseplant during the winter but it does best if kept cool (50F) and allowed to dry down between waterings. The danger here is watering a dormant rhizome will quickly lead to rot.
Treat this plant like a dahlia. While I grew them in pots for several years; I never took them out of the pot. But I didn't water them after they were in the house, staying cool and dry for the entire winter.
If you grow yours in the garden, dig up after a light frost and store cool and dry in sacks or dry peat moss. The trick is cool and dry.
For best results, grow this Zantedeschia or calla lily in a moist, fertile soil that is rich in organic matter.
It grows the best in full sun although a bit of noonday shade is ideal. If trying to grow the calla lily in a dryer garden (not a good idea) then it can tolerate more shade. This plant flowers best if regularly watered.
And if it has heavily flowered, in a good year you'll see some seed pods form behind where the flowers were. Here's how to germinate those seeds
You'll sometimes see Zantedeschia aethiopica 'Green Goddess' available and it is green leaved variety with a green spathe with white centre.Varieties that are readily found include:
*'Apple Court' dwarf growth habit, white spathe
* 'Aztec Gold' spathe bright orange to reddish
* 'Best Gold' spathe large and golden yellow
* 'Black Magic' spathe yellow, throat is black
* 'Bridal Blush' spathe is cream with pink tones
* 'Cameo' spathe is peach, black throat
* 'Carmine Red' spathe is deep carmine
* 'Dusky Pink' spathe light pink
* 'Harvest Moon' spathe is pale lemon yellow
* 'Lavender Petite' spathe is plum edged with blush pink
* 'Majestic Red' crimson red spathe
* 'Maroon Dainty' plum spathe with paler throat
An article about the real Calla Lily (Calla palustris) is here
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