Some greenhouse plants are appreciated more for their luxuriant foliage than for their flowers or food appeal. Taro, Colocasia antiquorum, is a good example and ideal for gracing a frost free conservatory or bay window. Luxuriant dark green, rhubarb sized, broad arrow shaped, leaves similar to those of an Arum lily, held on stems a couple of feet or so tall make a Taro plant an imposing sight. Several are magnificent and a wonderful backdrop for other more colourful or delicate flowering plants. Now there are several related ornamental species in this family but Taro comes with a huge advantage. For all the ornamental varieties are sold as choice plants so they do not come cheap. However Taro corms are sold as food in many ethnic stores, at food prices by the kilogram, so are remarkably inexpensive.
Taro is a tropical starchy root crop originally from the Pacific. At the base of the most distinctive foliage swells a large corm and or several cormels, much like potato tubers, which are cooked similarly and eaten. Found to do well with little trouble Taro travelled the world. In West Africa it became Old Cocoyam, reaching the West Indies it split into Dasheen and Eddoes. Dasheen like Taro and Old Cocoyam produces fewer larger corms, Eddoes more and smaller cormels, their foliage is near identical. Given the choice Eddoes are better as the cormels are smaller thus you get more plants.
With the original Taro, Old Cocoyam and Dasheens you get mostly single large corms, though these can be grown from their tops and the rest eaten. Be careful of the rough skin on corms and cormels as this may irritate. Plant cormels or the tops of corms barely moist gritty sowing compost in the warm and before long they throw leaves. Move on into potting compost, keep warm and moist. Finally big tubs of rich very moist compost and they make stunning specimens. You can even move these out for the summer to make strikingly lush features.
In a warm summer Taro does well outdoors, preferably in moist soil, but obviously can not stand any frost. Under cover in the warm Taro can stay lush through autumn and winter as long as light levels are high. But if it gets cold and dark the foliage dies down leaving the corms and cormlets, which of course can be divided up and multiplied, or eaten. But you can go one further; looking every bit the same in almost every way, but on anabolic steroids, is Tannia, Xanthosoma sagittifolium. Also known as Yautia or New Cocoyam, this really is remarkably similar but much bigger. Liking slightly less moist compost and needing really large tubs Tannia can tower over your head.