These are Colocasia & Alocasia plants commonly known as Elephant Ears Plant.
These plants are sun lovers and require a few hours of direct sunlight as part of their plant need - if they don't then often they will succumb to pest attack - usually spider mites, mealybug & aphids will be heavily infested on them adding more stress to the plant.
These are the Few Tips that I would like to share with you:
1) Identify which types are Sun lovers compared to Shade Lovers.
These are Sun lovers and require open bright sunlight.
2) These are also swamp plants and do require heavy watering.
Do place a container or a water catchment for the root ball to be water bound as not to wither if the medium dried out.
3) Occasionally check for Pest especially spider mite, mealybug or aphids and once the infestation is detected - spray the foliage with neem oil mixed with soap.
These are the Plants in my Collection:
Colocasia Species
1) Giant Taro - Colocasia gigantea 'Thailand Giant'
2) Swamp Taro - Colocasia esculenta L.
3) Black Taro - Colocasia esculenta 'Black Magic'
4) Taro - Colocasia esculenta 'Black Ripple'
5) Taro - Colocasia esculenta 'Teacup'
6) Imperial Taro - Colocasia esculenta 'Illustris'
Alocasia Species:
7) Black Stem Alocasia
8) Alocasia Cucullata
9) Xanthosoma sagittifolium