You may want to contact the manufacture of the perlite and ask them which screen they use for their horticultural perlite. For most purposes #6 screen (just smaller than 3mm) or larger will be a good size.

Pete,
Pictures you show in post #20 is what happens to my cuttings now.
I have drastically reduced the moisture content and eliminated fine particles.
Cuttings stop growing new white roots, (some cups were almost rootbound), roots take this brownish color, roots, appear dry like air pruned.
Cuttings newer complete pushing previously swollen buds.
Cuttings Just sit like this for weeks.
I have examined them and there is no rot.
The bark is perfectly healthy. Some were even green under the bark and juicy, other rather dry.
Some cuttings were dry and hollow like a pipe though.
How to explain this?

Perfect timing for this conversation as I have make a trip to Carolina Perlite to get a few bags for my orchid mixes.  Oddly enough my dad had made sifters for me a long time ago and they are perfect.  They were originally made for sifting fossils out of creeks but have been used for many other things since then.
Jon is right about s-moss having anti fungal, bacterial and molding properties.  At Wellsweep Farm I remember that they use living s-moss to root very difficult cuttings.  Orchid people use living s-moss to save badly root damaged plant so maybe that would also work for hard to root figs.  I know that one orchid grower uses some redwood fiber to re-establish newly imported orchids because of similar properties.  Not sure if any of my cutting are of the type that will be hard to root but maybe I'll play around with some of my orchid mixes if I run into issues.  What fun. 

I buy #3 locally, but it varies a lot, and some batches are mostly large particles, and some bags have more fines. I screen them all.

Jon, when you have time... :)  please post a photo of your tumbler/drum.

Harvey,

While not Jon I will show you how I screen the perlite.  I have a 1/8 inch screen and the mixer holds easily half a 4cf bag of perlite at a time.  Did two 4 cf bags this spring and took all of 5 minutes.  I have another 1/2 screen I use to screen the pine to get the right particle size for the soil mixes.  It is also my soil mixer, without the screen of course....put in the ingredients, flip the switch and done. It has yet to see any cement:)  I agree with Jon 100%,  the particle size makes a huge difference and those perlite fines and dust are very bad news.  

Thanks, Wills.  I'm tired of hand screening.  I don't know that I want to buy a cement mixer yet. Actually, I have a very heavy duty gas-driven one but couldn't get it started the last time I tried maybe 5-10 years ago.  I am thinking of using a plastic barrel and roll it on caster wheels that sit on top of a frame (in the old days, I did that for sorting chestnuts, not I have a long motor-driven one).

Harvey,

I bought it to make soil mixes...the perlite and pine fines screen was just an afterthought.  For $149 (on sale) it is hard to beat.  

I thought about getting one for mixing potting soil before but had previously heard or read that a rotary mixer like this doesn't do a great job because of the different density of various ingredients that can result to heavier material staying around the outside.  I assume that has not been your experience.

Gregg,

Yep it is a Harbor Freight.

Harvey,

If you over fill it perhaps but doing 2 cf (it is listed as a 3.5 cf mixer) at a time it mixes in seconds no issues at all.  You do want to mix first then add water if you are making a wet mix.  I add fullers earth to my 5-1-1-1 mix and it is heavy, it mixes right through.  Normally I put the peat in first and tumble it a bit with a couple of bricks in the mixer if the peat is lumpy.  Once the peat is lump free I take the bricks out and put the rest of the materials in and in under 15 seconds it is all perfectly mixed.  

I get free exercise mixing in my cart with a shove, lol  May give it a try, though :)

I use to mix using a tarp.....that mixer is one of the best things I ever purchased:)  

Jack, get the Aztec perlite at Grangettos. Quality is great and way cheaper than at Home Depot. I think I paid $10 for 6 cu ft.

Hi can_smokva,
If you have so much roots, than put them in a pot. With so much roots, they are no longer cuttings, but trees ...

Jdsfrance,
Although there are lots of roots the cutting has still not formed a hardened callus on the bottom cut end.
It was at least another month before it was fully callused. Treating it as a tree at this stage would only have lead to possible failure. The cuttings were bare rooted (easily) and up potted to 1-1-1 ratio mix of sifted Pine bark fines- Coir(peat) - sifted Perlite. Pictures of their progress are in this topic... http://figs4funforum.websitetoolbox.com/post/show_single_post?pid=1278056001&postcount=1

The sifted Pine bark and sifted Perlite made a remarkable difference in the increased volume of healthy roots. The particle sizes were between 1/4" and 1/8". 

At 3 months old...
 

Can_smokva,
The bottom of the cuttings were cut just below the bottom node so that they would not develop a "hollow" when the pith rotted out and the tops were sealed with wax.

Milehighgirl types -I was at a local greenhouse and they are selling #2 and #4 sized perlite. It seemed to me that the #3 would have been the best size. Does anyone have any idea about the sizes of the perlite?

When i used to make my own mix at the time i was buying #4 and took picture of it
with coins to show the particle size.
Hope this helps.

I sifted the "larger" bits from a bag of Home Depot thermo-rock perlite with gutter guard mesh and mixed 50/50 with mg seedling mix, which has a tiny amount of perlite in it. I was amazed at how readily it drained. It seems these high flow rates would require frequent watering, bordering on hydroponic?
I reduced the perlite to slow the flow a bit (it was like the water was running straight through gravel) out of concern that no water was being retained. Trying to wrap my head around this. I guess you balance desired growth rate, watering schedule, and compatibility/shock when transferring to the ground in your area (I have heavy red clay)? I imagine Jon is watering daily, maybe twice daily?

I also noticed the Jiffy seedling mix had no perlite, only vermiculite and peat, but I'm thinking vermiculite is a bad idea all together for seedlings and cuttings, and adding perilte to that mix won't help since it also absorbs water. Thoughts on usefullness of the jiffy mix?

I think I read somewhere on this site that as soon as you get bud break on a cutting in the rooting stage, to transfer to a pot even if there are no roots yet.

Gofigure, seems the high/coarse perlite ratio is best suited for high-humidity greenhouse environment where one hits with a mister or shower-hose somewhat frequently. Otherwise root rot would be devastating. Guessing you'll have to adjust for your own growing environment. I know some of our southern varieties, once they take off, crave much more water than quick draining soil would permit. I think some of the LSU varieties could live in a mud puddle and be happy as clams :)

Thanks. I'll be adding an LSU Purple and probably a Hardy Chicago very soon.

Jon I think you may have just solved my problem.  I have recently been losing a larger than normal percentage of my cuttings to root rot.  My potting mixture recipe had not changed.  I had been working from for a large bag of coarse perlite that I have had for a few years.  In December it finally ran out and I just went a got a few small bags of Miracle Gro perlite from Home Depot.  After reading your post I tried sifting the Miracle Gro perlite and saw how much fine material was in there.  I went out yesterday and bought a 6 cu ft bag of Whittemore super coarse perlite from a local nursery supply.  I sifted some and mixed up a batch of potting soil with coarser sifted material and the improvement in drainage was significant.  Thanks for the info.

Wills, I decided to give it a shot!

I went to Harbor Freight yesterday.  Unfortunately, the cement mixer was not on sale, being sold for $209.99.  I asked a supervisor if he had an idea when it might go on sale and he said he didn't know but that I should receive a 20% coupon within a month.  He then mentioned he had an open box version in the back for $100.  I asked him why it was returned and he said he didn't know but that he had plugged it in and it ran.  I bought it and ran it for a little bit.  Not very well made but more than adequate for this purpose.  I don't plant to drill holes into it to bolt on the screen like you did since I might use it for small concrete jobs.  I will use a make-a-clamp (big hose clamp cut to length, sold in long rolls, already on hand).  Thanks for the idea!

 

Harvey,

Awesome:)  Not sure how long it would last with concrete but potting soil does not even give it a work out.  The clamp should work well.  You got a very good deal on it.

So I purchased a huge bag of #4 commercial perlite and went about sifting. I have a 1/4" x 1/4" hardware cloth sifter that I use for other purposes. I was surprised that eventually all but a hand full of chunks went through the mesh. Am I being too diligent? Just a few shakes and that's good enough?