There are a few different hikes up Table Mountain from Kirstenbosch gardens but the most well known is skeleton gorge.
The great thing about hiking on Table Mountain is the different character of the trails depending on where you hike up. Kirstenbosch gardens are on the South East side of the mountain. This side is recipient of far more rain. Thus the trails on this side ascend through thick indigenous forestry and many follow streams which continue to to run throughout the year.
About half way up Skeleton gorge there are a series of 5 ladders. Following these the trail follows the stream bed for about 20 minutes.
Immediately following heavy rainfall it is best to avoid this route but for most of the year it is perfectly possible to keep your feet dry.
After another 20 minutes of climbing just before reaching the top of the gorge you get above the trees and can enjoy spectacular views over False Bay and towards the wine lands.
The top of the gorge is at 720m. From here there are a number of options. The most classic is to continue along smuts track towards the plateau. The highest point of Table Mountain is found at the far East of the plateau at a height of 1086m. Thus there is more climbing although more gradual. Once out of the trees the hike is through wonderful fynbos with views that get better and better at each stop.
The surface area of Table Mountain is 56km square and home to 5 reservoirs as well as numerous peaks and gorges. The imposing flat plateau overlooking the city is a small part of the mountain. The vegetation changes throughout the hike with variety and diversity that is outstanding.
For averagely fit people this is a +/- 5 hour hike from the gardens to the cablecar. If the cablecar is closed the quickest route down is Platteklip gorge. This is a steep and unrelenting staircase with remarkable views North so of the city and Table Bay.