I will be in Cape Town for just one full day on Saturday, March 1, arriving the day before and leaving the day after. Are there some really good areas around there (say, within 50 miles?) for landscape photography? Not interested in flowers, but trees, beaches, rocks, cliffs, land-meets-sea, etc., would all be good.

Any advice on specific locations in the vicinity of Cape Town will be much appreciated! Many thanks. :)

A friend of mine use to live in Cape Town for many years. What I saw of her photos, you'll have plenty to photograph. Don't worry, just explore with your camera. Be mindful that there is crime due to poverty, so you must assess any situation and location. Have fun.

I'm Ex Capetonian, and there is plenty of oppurtunity. The whole of the Cape Peninsula is very picturesque and the bowl of mountains that surround Cape Town itself (Hottentots Holland Chain) are also great. The West Coast is pretty flat with long Sandy Beaches and good views of Table Mountain (the stereotype image is still worth doing). The East Coast being more montane and rugged.
Some 'scapes' worth persuing might be Hout Bay (Chapmans Peak Drive), Bettys Bay/Kleinmond (1hrs drive), Blouberg (for Table mountain across Table Bay). I can go on for hours but if you want more specifics then PM me

Cheers
Phill

Excellent advice! Thanks, Phil, for the specifics and thanks for your help, too, Pinholemaster.

Sounds like a I need to get a good map as soon as I get there and maybe a guide for the day to use my time most effectively. Thanks again. :)