The cultivar ‘Coffee cups’ is a plant that is hard to link to the common edible yam, Colocasia esculenta. It is unique in many ways due to the shape of its leaves – they are folded in a way to look like a cup that is capable of holding small amounts of water. The typical yam leaf is shield-shaped and flat.
It is an interesting plant to have because the ‘cups’ actually collect rain water during wet weather. Very engaging to watch, one can see as each cup fills up with rainwater, it eventally yield to the weight and volume of the water by bending their petioles to empty what they have collected. The leafstalk then springs upright again to start the cycle all over again. That is a reason why I have it in my community garden so that people can be acquainted with this fascintating yam.
Before we jump to conclusions that this plant is a potential ‘mosquito’ plant, let me tell you that the plant grows best being bathed in the direct sunshine outdoors. The petioles of this delightful plant will then turn into a deep purple. The heat from the sun should be able to dry the water collected in the leaves within a day or so or that the heat from the sun would have been able to warm the water up to a temperature inhospitable to the larvae of mosquitoes. Well, before anyone quotes me for this, let me qualify that these are my hypotheses! If one is still worried, what one can do is to just tip over the cups to empty the water! It should not be too much work if there is one plant as there can be just that many leaves!
‘Coffee Cups’ was once a popular landscape plant that was quite exotic some years back. Demand and probably the ease of propagation has made this plant widely available and more affordable. In many sense, its ‘exotic’ status has been downgraded, making it comparable to those run-out-of-the-mill houseplants we can see on sale in local nurseries.
As stated on Plants Delights Nursery’s online page on this plant, ‘Coffee Cups’ was discovered by Indonesian botanist Gregory Hambali and brought to the US by aroid expert Alan Galloway.