A. All of the cases that I have seen of fig fruits drying out on the tree have been from a lack of water getting to the fruits. This can be from a lack of applied water, plugging drip emitters, damage to the tree trunk restricting water to the fruits, or an increase in tree size without the application of more water.
The first response a fig tree has to inadequate amounts of water is for the fruits to shrivel. This typically leaves the rest of the tree unaffected. The leaves look the same; growth appears to be normal but usually with a smaller or open canopy.
A fig tree receiving enough water will have a dense canopy. Oftentimes the canopy is so full you are unable to see through it.
|Fig fruits are full of water. The tree must receive adequate amounts of water and at the right time to produce fruit like this.|
Not enough water to a fig tree results in a more open canopy. It is common for fig trees receiving enough water to grow 6 or 7 feet in one season.
My suspicion is inadequate water. Trees get bigger each year. You either have to add more emitters, increase the size of the emitters or add more minutes to the run time. I would focus on this rather than to water more frequently.
As a test, try supplementing the water the tree gets by adding water with a hose once a week. Create a basin under the canopy, level, about five feet across and several inches deep. Fill this basin once a week.
Also figs do much better if four inches of wood mulch is applied under the canopy in a circle around the trunk with a diameter of at least six feet.