A minimum of 40 flight hours are required by the South African Civil Aviation Authority, of which 15 hours must be solo time. Most people at the club obtain their PPL somewhere between 50 and 60 hours - it depends a lot on your enthusiasm, time, willingness to learn, and of course, your pocket too.
By flying over weekends only, the average student takes about 9 months, but many students have taken less time. Flying full time, it is possible to complete the PPL in at least 3 months.
Self study and preparation before each lesson cannot be emphasized enough. Flying an aircraft is a serious responsibility, and it is important to go over what you have been taught and shown during your lesson, and what you will be doing your next lesson. This will shorten your training time and save you money,