Many members have discussed and posted their preferred mixes, the major ingredients of some are listed below for comparison to a few custom mixes...

Containers..
Miracle-Gro:     85% - 15% (peat - perlite)
Fertilome UPM: 85% - 15% (peat - perlite).
Pro-Mix BX:       85% - 15% (peat - perlite).
Pro-Mix HP:      75% - 25% (peat - perlite).
Fafard52:         60% - 30% - 10% (pinebark - peat - perlite)
5-1-1:              71.4% - 14.3% - 14.3% (pine bark - peat - perlite).
5-1-1-1:           62.5% - 12.5% - 12.5% - -12.5% (pine bark - peat - perlite - calcined clay)
Gritty Mix:        33% - 33% - 34% (pine bark - ganite grit - calcined clay)

Sub Irrigated Planters (SIPs)
BillsFigs:        100% Mushroom Compost
Miracle-Gro:   85% - 15% (peat - perlite)
Pro-Mix BX:    85% - 15% (peat - perlite)
4-2-1-1:         50% - 25% - 12.5% - -12.5% (pine bark - peat - perlite - calcined clay)

Several members have used commercial mixes with added portions of Perlite, Lava Rocks etc. for added aeration and or Manure Compost, Mushroom Compost etc for added nutrients and organic humus.

Its been my observation that container grown fig trees will grow in almost any medium but will grow faster and healthier in a well aerated mix. I use the custom 5-1-1-1 mix, there are many merits of this mix and with the addition of 1 part Calcined clay the water holding capacity is increased while maintaining the beneficial aeration. The mix is still good (reuseable) after 3 seasons of use. I used the 4-2-1-1 mix successfully last season in SIPs.  I plan on trialing 2 new mixes longterm, the 5-1-1-1 mix without peat as mentioned by Al Tapla in one of the discussions and a Gravel - Sand mix which Ive trialed successfully with fig culture.

What is your current potting mix recipe for Containers and or SIPs?



Links to info on potting mix ingredients...
 http://www.greenhouse.cornell.edu/crops/factsheets/peatlite.pdf
 http://www.turface.com/sites/default/files/landscape_brochure.pdf
 http://earthbox.com/earthbox-pdf/EB-WEB-INSTRUCTIONS_NEW-2.pdf
 http://earthbox.com/earthbox-pdf/replant-instructions-1.pdf

Archived discussions on potting mixes...@Figs4Fun
 http://figs4funforum.websitetoolbox.com/post/consensus-on-potting-mix-6416224?&trail=50
 http://figs4funforum.websitetoolbox.com/post?id=6704202

Archived discussions on potting mixes...@ GardenWeb
 http://forums2.gardenweb.com/forums/load/contain/msg0212444023053.html
 http://forums2.gardenweb.com/forums/load/bonsai/msg0219033011437.html
 http://forums2.gardenweb.com/forums/load/contain/msg1221344425812.html
 http://forums2.gardenweb.com/forums/load/contain/msg0323131520631.html
 http://forums2.gardenweb.com/forums/load/contain/msg0914024623640.html
 http://forums2.gardenweb.com/forums/load/contain/msg0921071615772.html

Pete thank you for collecting all this valuable information. One of the members mentioned to me that different kinds of sand (eg construction sand) have different levels of silica, have you ever investigated which is the optimum sand for container culture?

Its good to see someone with actual, extensive, experiential knowledge (not anectodal) posting about soil mixes.

Rafael,
You're welcome.
Silica is a beneficial mineral for plant growth.
I've not done detailed research on sand, but it should be coarse and clean or prewashed to remove salts. I use coarse Concrete Sand from a local Quarry, but have successfully used Play Sand from the home Improvement stores in small planters.
  .
Attached is a picture of an LSU Purple in a Concrete Sand potting mix.

Actually this topic was started to get some more real Anecdotal Information from members instead of conjecture (assumptions).

... So what are you currently using as your potting mix ingredients and in what ratios?

<edit>

Pete

What I was referring to as anectodal is information learned strictly from browsing the internet and not based in empirical observation. Any old fool can become an "expert" by doing that, but I agree there is nothing better than people sharing specific, detailed observations based on multiple growing seasons and different mixes. Oddly enough, I have had some great results in odd situations-varieties have flourished in mostly pro-mix with little fertilizer, or even just topsoil (a mistake I made with one fig tree over 3 years ago and could not backtrack on). This leads me to believe that not enough attention is paid to the general heath and vigor of certain varieties, which can compensate for poor choice of medium, or even flourish regardless of medium or fertilizer plan.

Pete,
thank you for all the valuable information.

Rafael,
That is the first hand anecdotal info that I'm looking to compile in this topic.... My experience has also been that they will grow in almost any medum,but will thrive with proper balanced nutrients and potting mix or soil structure.

Yes, any one can read, form opinions and conjecture without ever actually applying the information.


Aaron,
You're welcome.
What's your mix recipe? Thanks...

Mine has evolved around my own climate need.
I use Mirracle Grow  (75% PM and 25% Perlite) then I add Wood Chips  50/50 (50 MG/50WC), I add some Water Crystals in the mix as a moisture reserve for harsher hot days.
that's it. 

Aaron,
Thanks...

That ratio is;
4-3-1  50% - 37.5% - 12.5% (Wood Chips - Peat - Perlite).
BTW regular Miracle-Gro is usually only about 15% Perlite.

How long have you grown in this mix? and How have your harvests been?
Thanks.

Thanks for posting this Pete, great to have all of this in one place.

Your efforts are appreciated.

I've been using a commercially used blend by a greenhouse for annuals. Worked very well on first year plants (upwards of 4' of growth on most), but I'm not sure about long term use.

Pete, since this thread is concerned with container culture, I am also curious whether you or others have noticed any variability with how roots respond to different mixes, eg whether robust roots or heavily compacted roots correspond to particular mixes. Mostly, I have heretofore used a combination of promix and mushroom compost mixed with a bit of sand and dolomitic limestone pellets so far, but this year I am following McGinva's advice and using Fafard 52 plus some sand and limestone. I have Agway Pine fines too for top dressing, and I will be adding a mix of rabbit compost, leaf compost and homeade vermiculture compost plus glacial rock dust and Iron tone in spring as top dressing. I am expecting good results.

Kelby,
Thanks for commenting and sharing your info...
Do you know (can you find out) the approximate ratio of major ingredients?
It can be used in comparisons... Thanks.


Rafael,
IMO, visibly healthier vigorous roots (larger diameter tan to white) develop in the more aerated mixes. As the potting mix becomes denser the roots grow out thinner and darker.

Most ingredients can be categorized as 1) High Porosity / Fine / Water Holding, 2) Aerating / Large Particles or 3) Supplements and additives. Most mushroom composts fall in the high porosity group #1 with Peat and most sands. Group #2, Aerated is Perlite, Gravel and Lava Rocks. Group # 3 are the Mineral Supplements Limestone and Fertilizers which are a very small portion (although essential) of the mix ingredients.

IMO, you will get much better growth by keeping the Aerated portion of the mix greater that ~50%. This is not to imply that you won't get good growth in the denser mixes, Its just been my observation at several different fig growing locations that faster healthier grow results from a more aerated mix.

One simple way of testing your mix is to make a small portion at the designed ratios, then sift it through a 1/4" sieve to separate out the particles, the more aerated mix will have more large particles remaining above the 1/4' mesh.

Thank you for sharing this info, Pete.  Great info!
Here is what I used for my 5 gallon SIPs.  On some trees, I only used Pro-Mix BX and Osmocote but had outstanding results on both formulas.

5 parts Pro-Mix BX
1 part perlite
32oz (capacity) earthworm castings
1 heaping Tblspn Osmocote pellets (flower & vegetable 14-14-14)

Here is what I have been mixing.

-1 Bag EKO organic potting mix (1.5 cubic ft/42.5 L)  Ingredients off of bag: Peat Moss, Fir Bark, Compost, Perlite, Alfalfa meal, Kelp Meal, and Dehydrated Poultry Manure
-3 gallons Pine bark 1/4" screen
-1 blue bag (8qt) Epsoma Perlite, Screened

~1.5 cups Kelp meal

~1 cup Dolomite Limestone

~1.5 cups Azomite

~1 cup Plant tone 5-3-3

~1 cup crab shell
This year I made some tweaks to it and added an additional
~Heavy 1/2 cup Irontone
~1 cup Espoma Garden Lime

It seems like a lot of stuff, but it's all right there on the shelf. I mix it on/with a tarp and just go down the line with my one cup scoop..

Each time I up-pot I add a some Bio-tone starter plus to each pot, maybe a Tblspn for a pot smaller than a gallon and ~1/4 cup for a tree that will jump 2-3 gallons in size.
I started using the Bio-Tone in a couple starts last spring, I got a free sample package from a local nursery. Those experimental plants had better color and growth than their sisters(control) with all else being equal. These plants also exhibited more continuous growth vs growth spurts. So I started using it during every up-pot.

This year my plants had the best color(no lime green leaves) and universally healthy leaves so far and zero burn. I use a dilute hydro-organic fertilizer every 2-3 waterings as well. I imagine I could probably get  up to 30% more growth if I used Miracle Grow or Dyna, but I'm a purist and try keep it organic as possible and the annual growth is acceptable for me.

Pete, do you think that Kelp Meal would be a good source of silica as well all the other minerals it supplies?

Calvin,

I purchased a bag of azomite about a month ago with plans to use next spring when I up-pot some trees.  How much would you add to a 5 gallon bucket of Pro-Mix?

Hmm..maybe 1/2 cup to a heavy 1/2 cup? You can't really overdo it, the only way you could would be by adding too much ultra-fine particulate matter to the mix. I would look at it as...that should be enough for the plant to be able to extract whatever beneficial minerals it needs. The best way would probably be to do a few with some variance and record the results.

Frank,
Thanks for commenting and sharing your info.
I've seen the pictures that you've shared on the forum.

That ratio for SIPs is;
2.5-1 ratio     70% - 30% (Peat/5% worm castings - perlite)



Calvin,
Thanks for commenting and sharing you info.

Your ratio is approximately;
1-4-1 ratio      15% - 70% - 15%  (pine bark - Peat/5% additives - perlite)

I typically use the Bio-tone Starter only for 1 gallon and smaller containers. I rely on the Mycorrhizae of the Espoma-Tones in the larger containers. I've not used kelp meal alone, instead I rely on natural compost to return all the required trace minerals back to the garden. Soil, Sand, Clay and Calcined Clay are also good sources of available Silica, which is one reason why I added Calcined Clay to my potting mix recipe.

Thanks for the great info Pete!  I had no idea that MG was mostly peat moss. 

Aaron - you use actual wood chips, not bark chips?  Do you find you need to add extra nitrogen and the mix breaks down and compacts pretty fast?  i.e. have you tried it on larger pots where the mix needs to keep several years or just on smaller ones where you are up potting at least once a year? 

Phil, my wood chip pile is from neighbor's tree when they shredded it. (so, I guess it's mixed?)
I don't know how long I will be able to keep the up-potted ones in 3-4 Gallons. 
I have heard from others too that eventually it will settle , as the bigger mass solids decompose.
I do add liquid fertilizer in the water.
Haven't used all the other face stuff like gravel, cement sand, Azomite, Dolomite, shells and corals...YET.
I'm not there yet.

Pete, thanks for compiling those recipes and posting up some tried and true mixes.   I like to know what others are doing that's been proven to work.   This is a timely thread for me, looking at filling a lot of pots in couple months.   Calvin, I like that mix with the time-release organic materials, I've made some similar mixes as well, but geared toward annual veg.  I was thinking about something similar for figs, so it's nice to read your mix.  I've always included wormcastings as an additive for the probiotic boost.   I've also included biochar in some of my mixes, and see that as a good aerating component.

How about those figs!

Phil,
You're welcome, Thanks for commenting.



Zone5figger,
You're welcome, Thanks for commenting.
I haven't had reason to use much Bio char other than small inconclusive experiments, but have read that it works wonders for problem soils. I do however use the Espoma-Tone fertilizers, Gypsum and Locally sourced pulverized Dolemite Limestone which provide most of the nutrient requirements of potted Fig Trees.



Rich,
Thanks for commenting.