Posted: 08/07/2014 at 07:45
Mel, my elderly Book of Houseplants published by Octopus in 1978 says:
"Codiaeum (Croton) - (16-18C/61-6F South East Asia) Challenging plants that are available in many shades of orange, red and yellow, white, cream and purple-black, with some plants having all these colours in many shades present in a single leaf. In keeping with the majority of plants with highly-coloured leaves, Joseph's Coat is not at all easy to care for and will require the conditions that most tender plants demand and the skills of the experienced grower to maintain them in good order. In ideal greenhouse conditions plants will attain of height of 3m/10ft or more, by which time they are a truly magnificent sight; as a pot plant the usual height is 60cm/2ft. Maximum sunlight, though no scorching, is essential if they are to retain their exotic colouring, and it is also important that the soil should at no time be allowed to dry out. Liquid feeding of established plants once a week during summer must not be neglected, and it will be found that mature plants will require fertilizer at at least double the strength that the manufacturer recommends. To pot these greedy feeding plants into soil-less mixture would be a waste of effort, as it is important that loam should be included in the mixture. Propagate by means of cuttings about 13cm/5in in length taken from the top-most growth of the plant. Treat the severed end with rooting powder before inserting the cutting in a peat and sand mixture - the temperature in the propagator must be in the region of 20C/68F. Although conditions are not ideal, crotons will go on for a considerable time in a warm room that is well provided with windows."
I would point out that this book was written for the northern European market - I'm sure in your climate you don't find this such a challenging plant.
I hope that is helpful