If this is happening to trees that are coming from UCDAVIS then it is the fig mosaic.
If it happens to all tree from all sources then it is the soil mix.
I would caution you that pine bark as a high percentage to the soil mix will make the soil acidic.
Even if you put powder limastone it will be a while till it changes the acidity.
As you Probably know figs like slighty aciic to neutral to slighty neutral soil .So get a soil tester at Wallmart and taste the soil in containers following the instruction that come with it.
I hope you made enough holes on side Bottom of container for good drainage and for roots to get out.
My bured figs in 4.25 gal.containers are doing very well,all green some has figson them abundantly.
Some ispecially the ones from UCDAVIS are stunted in size with motled leafes due to fig mosaic but i can see they are fighting it off and some even manage to put out a few fruits.
I use :Half soil from My vegetable Garden(Has a lot of old manure in it),.25 hard wood chips on bottom for drainage,and .25 ,2 year old manure in top .
I also applied Some limastone and some Osmocote in top according to label.
But i do not use Pine bark for fear that i will make the soil too acidic.
It is working nice so far.
Hope this will HELP.

By the way:My soil in container tested at 6.5 acidity with the Wallmart soil tester.
I also used some superphosphate in top of my containers toghether with Osmocote.
_______I also want to warn people to use garden soil only if they think it is clean and is not infested with nematodes. I know mine is clean.I also want to note that i did not mix the soil with the manure and hard wood chips but set it in layers,First hard wood chips then soil and at the surface old manure and fertiliser.Other than that Everyone needs a lot of luck to grow anything.Regards

I don't think it is the pine bark. I pot all of mine in a pine bark mix and do not seem to have the same problems. I use a fairly coarse mix which allows the water to pour through rather quickly. When I was in Turkey and Israel last year, I saw fig trees growing in gravel, in the side of retaining walls, even from the second story wall of a bazaar.

~james

Thanks for thoughts, Herman and James - I'm inclined to think it's not *specifically* the pine bark though the ones with higher pine bark seem more prone to it. The reason I say that is that one of Paradise Nursery's mystery figs (which I didn't re-pot this year) is showing signs of stress out of nowhere, so that means it's not in the same kind of soil mix as the other ones. When I thought about it as carefully as I could, it seemed that the ones that had this, were those which had been under some drought stress within the past week to ten days (in other words, they'd undergone some drying out) and then been rehydrated, but what I can't remember is if I then gave any of these any feeding with a fertilizer solution too quickly after rehydrating, maybe it's a "burn" or maybe it's just heat stress to where they got too dry and some of the leaves didn't bounce back. But that doesn't even seem right to me, either, because of the amount of rain of late (and the one fig isn't buried, so it has good drainage, plus it's in part-shade after the very hottest part of the afternoon). The main thing I want to do is help these figs hold onto what leaves are left and then do what's best by them, by changing soil mix, adding something, moving them to different location, whatever. I'll go to Walmart and look for some pH tester, per Herman's idea - what's the easiest and cheapest method for short-term testing, and does anyone recommend any particular kind of pH meter for longer-term use? (I should really have one anyway, since I have all the potted blueberries and a few potted citrus plants, which are finicky on the "taste" of their soil.) Appreciate you all answering, on and off forum (got some encouragement and ideas emailed to me, too).

Sherry

The older leaves yellow first

Yet I'd thought (maybe erroneously) that to over fertilize a fig was a recipe for promoting too much vegetative growth, etc., and have avoided giving much even though they're in containers.

Sherry, if I remember correctly from gardening books, if the older leaves yellow first, it's a sign that N is needed. It's true for in-ground figs that they can become too weedy with added N, but potted figs are a bit different. Their available N is limited and that's always leeching away due to watering. The fast draining bark may be accelerating the leeching process, not to mention that as a "brown" it's tying up a lot of N in its own decomposing process.