I've not found a hat large enough to cover my big ears. After the freeze kills back the foliage on my colocasia, I whack the plants back to a few inches above the ground. When I say "whack" that's exactly what I mean. These are thick, tough stems, so arm yourself appropriately when you go out in the garden to bring down these plants. I dump a mountain of mulch on top for thick insulation against the winter cold. The colocasia esculenta 'Fontanesii' is rated for zones 7b-10 and grows between 6-8 feet high on black stems. The September blooms are a nice yellow with a papaya-like fragrance.
I have two of these big plants in the fragrance garden to help provide privacy around our dining patio in summer. They grow rapidly, especially with moist soil. That said, mine survived last year's drought with minimal drip irrigation. These huge plants are both deer and rabbit resistant because all parts are poisonous.Since I live on the cold edge of the hardiness zone, I have to protect my elephant ears during the winter months. Some gardeners around here (and colder zones) dig up the roots to overwinter inside in a garage or basement. My colocasia wintered over just fine last year with the mulch overcoat. The plants increased in size, but not enough to have to divide them. These were planted in spring 2007, so I may be ready to divide them next year.
Since the black stems have a deep red undertone, this colocasia looks good with companions that sport purple, lavender or deep pink blooms. I use buddleia 'Pink Delight' and monarda 'Blue Stockings' planted on the sunnyside of the colocasia. Underneath, I planted heuchera in purple. During May, before the colocasia are fully out of the ground and unfurled, there are mass plantings of Hyacinthoides hispanica (Spanish bluebells) that brighten up the garden.
If you are planning to include big leaves in your garden next year, think about providing enough space for these colocasia. Colocasia esculenta 'Fontanesii' should be planted in the spring after the last frost. Moist soil will give you better results. I've found the big ears will burn in the bright sun, so a bit of protection from the harsh afternoon sun and strong winds is highly recommended. In the next few days, I'll once again have to protect those big ears from the cold!