Here is an update

I haven't used any of the commercially available products, but have fabricated "pot Liners" for 3 gallon pots and half of my 5 gallon buckets. I have made them for 1 gallon containers, but they do not work as well in smaller sizes. The liners were made from spun landscape weed block fabric. They have worked quite well and make up potting or removal from containers extremely easy. I have been able to inspect the root growth without disturbing the roots, by turning the container on its side and sliding out the potting mix and plant together. They also work as advertised, increasing branching and growth of feeder roots.
1. The fabric is cut with scissors, the height of the bucket and long enough to overlap when placed inside.
2. The top of the fabric is cut even with the top of the bucket with scissors, after planting and filling with potting mix.

Pictured are several buckets with liners visible above the soil line.


The commercial Pot Liners are described at this website... http://www.treebag.com/pot_pruner.html

A You Tube video is here...

Love it Fedy, reminds me of when we lived in the Philippines.

After seeing Donna's hand sewn pots in person I decided to copy it and one particular commercially available starter pot to replace my 1 gallon container stage. Here's the final product. Its a 2 quart, 4 inch square, 8 inch deep air root pruning fig starter pot. Its made from spun landscape fabric. 10 bags fit in a standard 10 x 20 seedling tray. Attached is the build sequence with the directions. They are surprisingly sturdy and will open easily without disturbing the root ball.

1. Materials needed 12 x 18 piece of spun landscape weed barrier (commercial grade), scissors or razor knife, safety pin, stapler, tape measure, empty 2 quart container.

2. Wrap the fabric around the container (18 in. dimension) and place 2 staples top and bottom, keep the staple flanges (legs) on the outside for easy removal and up potting.

3. Fold over fabric to make bottom flap, align fabric top with top edge of 2 qt container, staple bottom.

4. Keep flap flat to bottom with safety pin.

5. The bag is complete and its free standing.

6 Plant rooted cutting in coarse, moist cutting mix, place in 10 x 20 seedling tray.

BTW it took a lot longer to type this than to make 6 of these bags : )

I cannot believe that I somehow missed Pete's update. This is awesome Pete. The safety pin at the bottom is good. How have they been working out for you?

The plants I have in "smart pots" are a lot bigger than the others. I have a KB that turned into a tree. My only concern is overwintering per Dennis above. I will put them in conventional pots before they go to sleep.

ps My Tim's light has 3 figs but it is not doing anything vegetatively. ???

Pete,

Wow what a great idea. Could you elaborate on how you make the pot liner out of the landscape cloth? (How is it held together on the bottom?)

Why does this liner work even though the solid pot is still there?

Donna,
They work quite well, they are easy to fill and plant... But they dry out too quickly from the exposed sides. The commercial ones are actually designed to be placed in the hollows of an 8 inch cinder block.
If they were placed in a container with sides (10 by 20 seed tray with 6 - 8 inch sides?), they would almost be perfect starter pots.

I would remove the two younger figs (ones at the top), they are probably using some of the plants limited energy. Its using resources to ripen figs instead of growing.


Figsation,
The pot liner is just a flat piece of landscape fabric. The Length is the circumference (3.14 x diameter of pot) of the container plus 6-8 inches for an overlap and the width is the height of the container. For a 10 inch deep 12 inch diameter container the landscape fabric should be 10 inched wide by 46 inches long. It is rolled into a cylinder and placed into the container , the container is filled with some potting mix, then the plant is inserted and potting mix is placed around the plant. The extra material sticking up above the rim of the container is cut away with scissors or utility razor. There usually is no bottom, but I did make a few circles out of landscape fabric and placed them in the bottom of a few containers as a test (inconclusive).

If you go to the linked website in post #27 its explained. It simply creates an air gap, which insulates (isolates) the soil from the container. Though the main advantage is promoting "root branching".

Just a minor technical point about the fabric barriers.  They do not "air prune" or "prune roots".  They entrap the apical tip of roots which results in the loss of apical dominance and thus the branching.  The three methods I've tried involve air pruning, entrapment, and chemical "burning" (copper paint product).  I like the coarse roughness and white exterior of the RootTrapper pots the best but they are pricey and difficult to re-use.

I have used Smart Pots for several plants, including garlic and shallots which worked well for me. Carpet Roses also did very well in a 3 gallon Smart Pot. After a year, I transplanted it into a 7 gallon Planter Pot. I may transplant it again since it is growing so well.

My Dogs are the Mother and Father of Invention: since they eat the leaves off of my young fig trees, I had placed the 5 gallon pot into a 15 gallon pot that is filled with very small amount of soil and worms at the bottom and about 3/4ths full of Perlite. So the 5 gallon pot sits on top of Perlite and is surrounded by Perlite. I had the idea that maybe the VdB roots would be enticed to reach down through the Planter Pot (not Smart Pot) holes and seek out the nice wormy soil beneath. I do not know if red worms eat roots. They have not eaten my Blackberry roots: they thrive with large handful of worms embedded into the soil. This week, I added wood chips into the Perlite and onto the inner 5 gallon pot because it so hot here that I have to water twice a day some days.

So, since I had the Planter Pots embedded inside the Perlite, I was thinking that I should try a Smart Pot embedded inside a 15 gallon Planter Pot filled with Perlite. I would not need the soil at the bottom since the concept would be merely to grow nice roots.