The start of Geocaching in South Africa:

The very first geocache in South Africa was hidden on the 14^th January 2001, 8 months after the 1^st geocache in America, and was hidden by team 'GPSFrodo'. The geocache was called 'GCZA01' (GC163) and was the 163^rd cache worldwide.
This cache was only found once by team 'Jors'. From their log:

Quite a feeling of acomplishment came over me as I saw the stash where it was hidden, the walk was well worth it!
...
I really enjoyed this, and will hide my own one of these other hot! days.
Lets keep this fun thing going!!

It took team 'Jors' another 9 years and 3 months to make good on their promise and placed a cache called 'GCZA01.2' (GC1RNAY) very close to the original first cache as a way to commemorate the first South African placement.
Team 'Jors' also has the very first South African swag item, a watch, as a Travel bug, which can be discovered at certain events.

The 2^nd geocache hidden was 'Sentinel View' (GC185) and hidden on the 18^th January 2001, only 4 days after the first one, and was hidden by 'Prof Charles Merry'. The geocache, or stash as it was known at the time, was first found by team 'netic' on the 3^rd of February 2001. From their log:

After a 40 minute hike we found the cache about 5 meters off the gps spot.
It turned out to be a spectacular view and well worth the walk.

This geocache is still active and still contains the original log book.  It is currently the oldest geocache in South Africa.  
The geocachers of Cape Town organised a 10 year anniversary celebration on the 10^th of January 2011. A video of the event can be seen here on YouTube.

The uptake of Geocaching in South Africa:

Geocaching was slow in taking off with team 'Peter Scholtz' and team 'Chris Smith' (now known as Chrisbloem) planting most of the geocaches around the South African landscape in the first 2 years.

In the 1st year (being 2001) only 72 geocaches were hidden.
The 2nd year saw 84 added and in 2003 there were a total of 250 hidden.
At the beginning of 2005 there were a total of 343 hidden, and then geocaching started taking off as at the end of 2005 there were a total of 703 hidden, almost doubling the cache count.

The perspectives of early geocachers were very different to those starting out now and here are a few examples:

On the forum (here) Brick stated this in January 2008:
"...In Mpumalanga Snowwolf placed a few, and those days 4 caches in an area justified a trip there."

Peter Scholtz's perspective on the game of geocaching here is a very interesting read.

Geocaches hidden over 2002-2018:

Cache count hidden per province:

*Note: This is the hidden count at the end of each two year period. This is NOT the same as the active (to be found) count.