Hi Bronx,
i cannot answer leaves to gallon ratio i just never paid that attention to counting leaves. ; )
But a half whiskey barrel or container of 25 to 30gallons can support tree you mention in mid paragraph long as you fertilize them .
I have some in those sizes at or near 6ft that just barely fit in under garage door when i wheel them in for storage.

I have some in 10 to 20 gallon containers as well that i keep near 4ft tall size and root prune > every 2 seasons.
The bigger containers i get away with no more than 3 seasons without root pruning.

Some types of fig trees are more aggressive in growth than others to keep in mind.

If your curious for example go to figs4fun forum you can see my trees by looking up my screen name its the same as here.
Membership is also similar here >

Martin
Chicago
Zone 5
Ebay ID Registered 1996 - Dieseler6z92
Member- Garden Web, Figs4Fun, Friends of The Fig Society

diesler: Thanks for the quick response to what probably is not a very important question.

After the last 4 years of growing some "ATREANO" fig trees (about the size mentioned in my posting), I have grown them in 25 gallon containers, and they are doing just fine. I also really do not count leaves. That was just a way of relating leaf mass to pot size.

Anyway, I really appreciate your input, and now, I'll go look at your pictures, as you've suggested.

Happy growing

effdeevee

Ah it is important question in my opinion and may give others idea's of what they like to do .
I may not count leaves but in past i counted figs and used tape measure to measure tree height out of curiosity. ; )
Now i just eat them.

For fruit trees, blueberry, and citrus my biggest trees are about 5ft tall and 5ft wide in 15 gallon pots. My figs aren't that big yet but I see no reason why they won't or couldn't get that big. This size is with one watering a day in summer.

With stone fruit I find fruit quality better if the trees are grown with a moderate water deficit. This results in sweeter fruit. I don't try to grow blueberries with a water deficit. I think figs are likely to be sweeter with a modest deficit but have no evidence yet.

fruitnut:

I just read your reply/opinion.

Can you give me a little more information/explanation of just what is meant by "water deficit" when speaking of growing containerized fruit/fig trees. Risking oversimplification, does this mean holding back watering as fruit ripens, to the point of slightly stressing tree? I assume that this will concentrate sugars in fruit.

Further information would be greatly appreciated.

Best regards,

FDV

FDV:

It's difficult to tell on potted trees just how much water deficit is taking place. But my number is that water use of about 75% of "full" water is about right on stone fruit. I have been able to increase brix by 5 to as much as 15 points on average, more on individual fruit. For instance Honey Fire nectarine is listed as 13.3 brix in the patent application. By growing that tree in a pot this year 12 fruit ranged from 22 to 33 brix, twice as sweet.

I let my plants grow as large as they will in a pot in spring. Then I don't increase water in summer. Don't know how much deficit that entails but the trees quit growing in pots much quicker than in-ground.

The primary take away is that with some fruit, probably including figs, a vibrant vigorously growing plant will not result in best eating quality.

Here's the reason why. When a plant has the opportunity to grow at a water deficit it increases it's osmotic potential in order to remove water from increasingly dry soil. The way a plant increases osmotic potential is by increasing sugars in all tissues including fruit. If it didn't the fruit would shrivel up as the soil dried. If you make the deficit too severe or too rapid, the fruit will shrivel and leaves will drop.

So slow vegetative growth but not enough to drop leaves or shrivel fruit prior to fruit maturity. In a pot you can't just cut off water suddenly. That doesn't allow the plant time to adjust. The plant must get water regularly but less than full water.

fruitnut:

Thanks for taking the time to elaborate on your original comments. Very interesting info.

FDV

FDX:

Figs do have one important difference from many fruits. They may be partially dehydrated after they mature. That may take the place of some deficit before maturity.

My somewhat limited knowledge of figs is that the best fruit is grown in climates with wet winters and dry summers, I'm thinking Turkey mainly. Dried Turkish figs are superb. Many of those figs are grown without irrigation. So the tree has a long slow increase in water deficit as the crop matures. This makes for very sweet high quality dried figs, and probably fresh as well.