Hi. I've just built an elevated tub (about 5 ft. above ground level) to give me more space in my small greenhouse. I water my figs from the bottom of the pots, upwards using my existing aqua-ponic (fish water) setup. My question is pretty much unrelated though. Some of my 3 gallon pots are only 2/3 full of soil, would it harm the plants to fill the pots to nearly the top with additional soil covering the bottoms of the stems to promote better rooting? They will be overwintered in the greenhouse. I'm a newbie and most all my figs were started last November (losing the majority of my cuttings to over watering). So, will covering the stems with dirt an  additional 5 or so extra inches cause damage or kill them? I've included a picture of my watering shelf with the plants in question. Thanks for your advice in advance.

I've done it that way, Noel, and it was fine. I scrape a bit of bark off of the portion of stem that I am going to bury, to encourage rooting. Never failed. The other option is to lift the plant out, and add more soil to the bottom of the pot.

Lifting it.  LOL I didn't even consider that. See why I love this forum. Thanks Gary! 

BTW Alan Hows that "Malta Purple Red" doing? Hows the taste?

Just adding the soil will be OK. Soak the added soil from the top at least once if you are normally watering from the bottom. 
It has always worked fine for me.

I'm surprised to hear that adding soil above the "crown" of a growing tree does no harm. I was recently reading that in general tree crowns have a type of tissue that is different from both roots and trunk and should not be buried. Leave it to figs to be the exception :-)

If the portion of the wood just above the crown is capable of rooting before rotting the it is safe to add soil. The problem is not the soil itself but the moisture that will rot the part above the crown if it does not root before rot. The potted fig plants will easily root with moist soil before rot.
Surf the forum and you will find example of air-layering very thick branches of fig trees above the crown.
When wooded area are leveled in landscaping project, mature trees are left with bowl like open area not to cover above the ground to avoid rotting but it may not be necessary for species like willow trees because they most likely generate roots even when reasonably mature. 

Hi,
Soil under the roots is more important so that the roots can use it. So at least lift it up and use half dirt under and half dirt over.
I like adding a bit of dirt on the top because while watering, the trees can get sort of wounded and burying those wounds in the dirt is good.
But then I just bury 1/3'' - 1cm but not more .