Donkey ears are also known as Kalanchoe gastonis-bonnieri.
From Madagascar they are said to be naturalized in tropical areas of Australia.
The initially erect round stems can be 30 to 50 or 60 cm long and 1.5 cm thick.
The pale green stems may have reddish areas at the top and a waxy white coating.
Usually the only branches are in the inflorescence.
The fleshy opposite leaves are typically concentrated on the lower part of the stem sometimes
forming a tight basal rosette.
The short wide petioles clasps the stem.
The ovate to lanceolate blade can be from 15 to 50 cm long.
The tip is pointed, the base wedge-shaped and the edge has small teeth or lobes.
They are green with a white coating especially when young making them grey-green.
There are short purplish-brown streaks across them and the notches on the edge are coloured.
Plantlets or bulbils grow from the notches near the leaf tip.
These grow into new plants when the leaves fall or the stem bends over and touches the ground.
The branched terminal inflorescence holds dense clusters of drooping flowers.
The branches can be up to 8 cm long with the terminal flowers opening first.
Flowers are on a pedicel up to 1.5 cm long that has tiny bracteoles on it.
The flowers, up to 5 cm long have 4 sepals and petals.
The sepals are fused into an inflated tube up to 1.5 cm long with pointed lobes up to 1 cm long.
Initially green the exposed outer surface becomes reddish.
The petals are fused into a corolla tube around 4 cm long that is constricted above the ovary.
The pointed lobes, with some glandular hairs are around 1 cm long.
The corolla starts a slightly greenish yellow with a red margin on the lobes and red lines running
down from between the lobes.
It then becomes a salmon colour sometimes with more dark reddish lines.
The inner surface remains yellow.
There are 8 stamens inserted low down on the corolla tube.
The anthers lie just outside the tube near the bases of the lobes.
The superior ovary consists of 4 carpels.
The fruit consist of 4 follicles with numerous ovules.
Towards the end of flowering the leaves wilt and the plant dies.
New plants grow from the fallen plantlets.