The exotic Zantedeschia is not hardy. After a life of luxury on the balcony, terrace or windowsill, the indoor calla would like to hibernate in peace. Read how to do it in these winter tips.
How do I overwinter a Zantedeschia?
To overwinter a Zantedeschia successfully, provide bright, cool and dry conditions at 10° to 15° Celsius. Water sparingly and do not fertilize. After winter rest in December, increase the temperature, repot the plant, remove dead parts and start watering and fertilizing.
Zantedeschia overwinter bright, cool and dry
The elegant Zantedeschia aethiopica comes from South Africa. On this side of the globe the climate is determined by the regular alternation between the rainy and dry seasons. A sweltering summer is followed by a cool, frost-free winter. The successful overwintering of a calla simulates this cycle:
- Place as a patio plant: from temperatures of 12° to 15° Celsius
- Relocate as a houseplant: from October
- Light: winter brightly with at least 1000 lux light supply without direct sun
- Winter temperature: winter in a cool place, ideally at a constant 10° Celsius (optionally 12° to 15° Celsius)
- Winter care: water very sparingly and do not fertilize
You should prescribe a change of location to a bright, cool winter quarter for all indoor callas. If you expect your Zantedeschia to be grown indoors all year round at temperatures of around 25° Celsius, you will look in vain for the picturesque flowers.
Wintering at the end of December – How to do it
The most beautiful Zantedeschia varieties bloom from January to May. So that the noble flower festival can begin on time, the winter dormancy ends shortly after Christmas, when most of the other potted plants are still dormant. How to awaken indoor calla lilies from hibernation for a lavish blooming season:
- At the end of December temperature increase to 18° to 20° Celsius
- Repot Zantedeschia in fresh, peat-free substrate (€28.00 on Amazon) over a drainage made of lava granules
- Brush the rhizome, cut off dead shoots and leaves
- At the same time as the flowering period begins, water more frequently with soft water
- Fertilize weekly from January to May
From mid-April to autumn, the Zantedeschia will be happy to keep you company on the balcony or terrace. In a sunny to semi-shady location, the South African flower beauty gathers fresh strength for the next winter.
Tip
The new Zantedeschia variety Crowsborough is the first hardy garden calla lily with a summer flowering period from June to August. With the right winter protection, the frost-resistant tubers can overwinter in the bed and do not need to be dug up, like cold-sensitive dahlia tubers. A thick layer of leaves and coniferous twigs protects the rhizomes from the bitter cold and moisture. Before that, stop the water and nutrient supply in late summer.
