Kumara plicatilis flowers are visited by a variety of insects, including bees and monkey beetles, and by nectar-feeding sunbirds, all of which contribute to the pollination of the flowers. The seeds are dispersed by wind.

Kumara plicatilis is often seen growing in areas that are not prone to burning, but they are able to survive fast-moving fynbos fires. Its thick fleshy leaves contain a lot of moisture and resist burning, and it has thick corky bark that protects it from the heat of fires. It's a good plant to choose for a garden in a fire-prone area as it will not pose a fire-threat to the house.

Werner Voigt observed intensive debarking caused by rock hyrax (dassies) on Kumara plicatilis at Goudini during 2009. These agile animals climb to the top of branches where they first chew off the protective corky layer to get to the inner parts which are fibrous and a whitish colour. This contains a lot of water and is eaten right through until the stems collapse and fall to the ground. This behaviour presumably is associated with periods of drought. It was also observed that stems that have fallen to the ground readily root if there is sufficient soil and shelter close by. Those that fall on bare rock simply perish in the sun.