Everybody will give you a different answer. Many have it well thought out. I'm lazy, I do it fairly simple. First 10-10-10 is about the worst stuff in the world. Ratios are way off not just for figs, but for any plant. I use Dynamite control release. It says it lasts 9 months if temps are under 80F. My experience is it lasts about 4.5 months, which is not bad. NPK ratio is decent and includes micro nutrients. Osmocote says 6 months, so lasts about 3 months. I also add Plant-Tone or Garden-Tone once a month. I start in April. The start of the season is where they do the best. I'll put my trees against anybodies. The biggest fig this year started from a cutting in February is now 8 feet tall, first year. I have a few 6 feet, and a few 5 feet, and the rest are 4 feet tall now. A few smaller that i started later. I also never add lime. I like the pH between 5.5 and 6.5. Hard to do if adding lime. I use gypsum in my homemade soil mix. Takes care of any calcium needs, as does the fertilizer, more is not better at times, the gypsum is probably not needed, but it tends to stay neutral, as pH is really important. Lime can sky rocket your pH.
Here is one of my first year cuttings, unk. Teramo, photo taken about 6 weeks ago.

This photo was about 75 days ago. Red Lebanese (Bass)

This is the 8 footer, photo taken 10-06-16 Sweet Diana. Not the best photo, as it was backlit by the sun. This one is in ground, but got the same fertilizer regimen.
