Being that this is towards the beginning of the fall season for you guys in South Africa, you should be ok watering this species normally for now.
This species is from Luzon, Philippines. If you look up the climate of the region it will show you how drastic of a change it is in precipitation between the winter months and the rest of the year. It isn't completely dry, but it doesn't rain often at all during those months. The dry-ish spell lasts for about 4 months.
So, in other words, when winter rolls around, forget about it. If you happen to water it once or twice in a month, that's fine.
This link might help you out:
Weather and Climate - Philippines