Water the ground-grown ivy to keep the soil slightly moist. Allow the top 2 inches of the potted ivy's soil to dry before watering. Drench the soil, until the excess water runs from the bottom of the pot. Allow the pot to drain completely before replacing the saucer underneath the pot.
Provide the tropical ivy with humidity indoors by placing a humidifier close by. In lieu of that, fill a shallow tray with pebbles, cover them almost completely with water and place the tropical ivy's pot on the dry portion of the pebbles.
Place the indoor-grown tropical ivy in an area of the home that receives filtered sunlight from a south- or west-facing window or in direct sun in a north or east window.
Apply an all-purpose houseplant fertilizer to the soil once a month during the growing season. Fertilize outdoor tropical ivies with 12-4-8 fertilizer, at the rate listed on the package, in spring and in fall.