Take a look at the Silverhill Seeds online catalog. You probably won't get much info on the exact location (Eastern Cape vs Natal) but you will be able to tell if it is a summer-rainfall plant or winter-rainfall plant.

The Eastern Cape most definitely does have a more subtropical/humid influenced climate, as well as widely varying rainfall from year to year. This results in many plants from this part of South Africa having great garden potential as they can handle occasional drought as well as regular garden watering. Unfortunately, this doesn't always translate into having good freeze resistance, and many Eastern Cape succulents will still need protection from freezing conditions. I would suggest that you visit the web site for the National Botanic Institute of South Africa to get a better handle on the range of climates and habitats for specific plants. Go to www.plantZArica.com, and in particular, go the the section on different climatic/plant communities that are reprints of articles from the Journal. These give very good descriptions of many plants that come from the Eastern Cape, as well as the soil/climate conditions under which they grow. Not particularly freeze tolerant, but succulents such as Senecio mandraliscae, Cotyledon orbiculata, and many Aloes may fit the bill. There are also quite a few Euphorbias which love heat and humidity. If you can get your hands on a copy of The Guide to Aloes of South Africa, this also lists locations/habitats for Aloes which come from summer rainfall/high humidity parts of South Africa.

You do need to be careful that not all plants from summer rainfall areas will also take high heat and humidity in combination, as many come from high elevations such as the Drakensberg Mountains, with cooler summers and relatively dry cool to cold winters. Aloe polyphylla is one example, and would quickly die with Louisiana conditions, but loves it here in San Francisco, even though the rainy season is reversed to its habitat.

Hi, I live in the Eastern Cape of South Africa and can tell you that it is very rich in succulents and Euphorbias as well as some Aloe species. If you like the haworthias you might also like the gasterias. Please ask if you have more questions.