Hi yellow,
There's a long answer coming up!
My previous experience was a 5 year apprenticeship on large properties and estates in the 80's. I had a regular career up until 2 years ago when I decided to do something I loved. I started working as a gardener and at the same time signed up for the level 2 Principles course 1 day per week. This is the biggie. 30 weeks with a recommended 6 hours additional study per week. At the end you sit 8 papers over two days. This was our perspective when the course started.
Of course, reality soon kicked in and for most on the course the 6 hours was hit or miss and probably closer to 2 hours! The days on the course were fantastic. I learnt so much! Every day I was coming home and sharing interesting facts with my DW. I took notes and there were copious handouts. As the weeks passed by it became obvious that we were accumulating a ton of information and none of it could be discarded as we had all the exams at the end. Furthermore, in the exams we would be required to memorise and provide proper plant names in Latin in various groups and subgroups I.e 10 evergreen trees, 20 plants suitable for summer bedding, 5 alpines, etc, etc. My plant list extended to 150 plant names. All of us on the course ignored this elephant in the corner until we were into the 3rd term. For me the only way to cope with this list was to have an immovable deadline! In the end there was little problem with the lists and I was quite angry that we used so few plant names having swotted the lot.
The exams were divided over two days. Short exams were 40 mins 2 per day. Long exams 80 mins 2 per day. It is mentally fatiguing to get through the two days. To pass you need 60% min in every exam.
Exam in June. Retakes in Feb. I was lucky and passed all first time. Pass rate for the group was around 70% I believe.
The level 2 practical was half a day per week. Practical tests were things like seeding, double-digging, pruning, etc. Plant ID tests were familiar I.e. 10 evergreen trees, 5 deciduous shrubs, etc but this time you have the 10 or 5 samples in front of you and you must identify each one correctly. Having done the Principles course this one was straightforward.
Get the two of them and you get a diploma - one of either gives you a certificate. Most people who were able did both courses at the same time. I did them a year apart because I'm an idiot.
I worked as a gardener all the time I was doing the courses.
I was competent before I started the courses but I was not confident. What the course gave me was confidence. I would also say that I knew WHAT to do around a garden but after the course I also knew WHY.
If your aim is a career switch then I think you need to find out if you can take the physical grind of the job before you commit your time and money to the course.
If you want to do the courses for personal development and you have the time and money then go for it! You will learn so much.
Finally, at my college the day course cost £900 and the half day course £600. Add in lost earnings and it is a significant investment!
Note: the day course can be done over 2 years as an evening class. The positive is that you cover each module then do the test. So you can discard stuff as you go along and only need to revise the current topic.
Phew! I think I covered everything. I hope this helps you.
Best rgds,
Steve