I thought some might like to read about some of my experiences and things I've investigated lately regarding potting mixes.

I was unfamiliar with Pro-Mix HP potting soil until reading about it written about highly by several members here.  I purchased a compressed bail at Lowe's a few weeks ago and have used it for some of my rooted cuttings which I've potted up.  My prior cuttings were potted up in a variety of mixes I already had on hand, all of which had a lower percentage of perlite in the mix.  I've potted up a little over 100 cuttings over the last six weeks or so and have lost a few which I believe was probably due to over-watering which led to rot.  One thing I've noticed about the Pro-Mix HP is that it seems much more difficult to over-water due to the high perlite content.  Some pots also got a little drier than I like but I've caught them in time.  Overall, I like the Pro-Mix HP over what I've used before but it is pretty pricey, costing about $35 for a 3.8 CF.  I've purchased the version with mycorrhizae

I previously had some bulk mix (10 cubic yards) made at a plant in Sacramento, Redi-Gro, and drove there today in a quest to find some coarse perlite (the stuff sold by Home Depot isn't coarse enough for rooting, IMO).  They were out in 6 cubic foot bags but did have a 62 cubic foot bag but that wouldn't come close to fitting in my pickup since I've got a utility shell on the bed!  This is a very large potting soil plant (very large loader, several big 18 wheeler trucks, probably 3-4 acres under roof for mixing, etc.) but they still deal with small orders so I picked up a bale of Pro-Mix HP ($32) and also asked for a comparable Sunshine product and was sold Sunshine #4 ($32.30).  Both have 65-70% peat and the remainder perlite.  Pro-Mix had the mycorrhizae and a wetting agent and lime.  The Sunshine #4 has limtestone and is organic.  Both seem similar in appearance.  I can add mycorrhizae separately to the Sunshine and add slow release fertilizer as needed.

I spoke with their agronomy specialist (forget her title) whom I had worked with before.  I asked for a quote for a bulk mix of 5 cubic yards of something similar (5 yards is their minimum order).  I asked if they ever use an coconut coir and she said they are using more and more of it as it is a little les expensive than peat and it has greater porosity.  I asked her about the pH of coir and she said she believed it was fairly neutral.  She asked if I wanted any sand and I told her that I saw now benefit in it since it has limited nutrient holding capacity and the perlite helps ensure adequate drainage.  She  said one benefit is the addition of weight to help pots from blowing over.  Since my young plants are in my greenhouse and I might end up shipping some at some point, I didn't want the weight.  I didn't write it down and will be receiving a spreadsheet with the pricing, but I believe we settled on 40% peat, 35% coir, and 25% perlite with 3 pounds of dolomite lime per cubic yard.  When I asked for a guess, she thought it would probably run about $50 per cubic yard.

My prior mix with this plant and many of the others I've used are made with fir bark.  I asked her if they ever deal with pine bark and she said that the bark they use is actually a combination of fir and pine bark direct from lumber mills.  I previously financed a few loggers and know that here in our Sierra Nevada range the majority of the lumber harvested is Douglas Fir with some Red Fir, Sugar Pine, and White Pine (don't know that those are listed in order, it's been 25 years since I worked in that field and it was just a small portion of my clientele).  I told her that plants in my prior mix of a few years ago didn't really thrive and asked her if she was aware of any problem with the tannins in bark and tender roots of cuttings.  She said that she did believe it inhibited growth but that when moving up potted plants into larger pots, they were able to do fine.  I'd like to know if anyone has seen any good information on this.  I know that a lot of people have used pine and fir bark but I wonder if it is really ideal.

By the way, I ended up getting my perlite.  The Redi-Gro woman referred me to a "indoor garden supply" (catering to "medicinal marijuana" growers, etc.) facility nearby.  I've been to a few of these types of places before but nothing this large.  I estimate the place was 100' x 200' with a huge selection of pots and maybe about 8 kinds of perlite. I bought a 6 cubic foot bag of coarse perlite for $22.50 which was a decent price, I thought.  I also bought a 3 gallon RootBuilder pot to try with one of my figs and also a 15 gallon fabric pot for a jackfruit I have in my greenhouse.  I'd guess they had at least 100 different types of pots from less than a gallon to 60 gallon.

Harvey, you should give Foxfarm ocean forest a try for comparison. I've used Pro Mix and Fafard #2 in the past and began using straight Foxfarm to pot up rooted cuttings a couple years ago, and swear by it. I also use it for my vegetable seedlings. Strong and sturdy growth. Works great for me.

Regarding pine bark fines in mix for young plants- I found faster growth in my fast draining mix( 2 pbf,1 perlite, 1 promix bx) vs pure Promix BX. I think it is only because the roots are healthier from better aeration.

I get my Promix BX 3.8 bales for $27-28 and if I buy 10, $25 each at a co op.

Your perlite price is very good. My coarse perlite costs $18 for 3 cu ft.

I am also experimenting with cloth pots this season. I like what I see so far especially in my 1 gallon newly rooted cuttings. I bought 1gallon - 20 gallon pots. I think it will cut down on repotting and root pruning plus better root health.

Hi Scot, thanks for the input.  I did think about Fox Farm since Redi-Gro sells it also.  However, for the quantity I'm looking at, I think it's just not a feasible solution because of the higher price.  Even the $32 price gets pretty bad when wanting to pot up a couple of hundred figs (and, possibly, hundreds of chestnuts).  Eventually, most of my figs will go in the ground while some will be sold/traded.

Jason, thanks.  I have a bale of coir already on hand and might mix some of it, along with more perlite, to some of the other mixes to see if I notice any difference.  I'm a little worried about it drying out too quickly, though.  My greenhouse is regularly getting up to 90F by 10am (before the cooling fan kicks on), so the more developed plants are using up a fair amount of water.

Yes. That mix is for youngsters. I use 2-3 pine bark fines, 2-3 Promix, and 0-1perlite for older trees depending on how big and thirsty they are.

Jason ,
What brand are the pine bark fines you are happy with ?
They are a little hard to find up here.

Here in the NW we have tons of pine trees dropping needles ... could I compost them?  Since I started using the needles for my potted blueberries they are doing much better, but they are acid loving plants... I didn't think figs like that acidity of the pine.  I see the soil with the needles are is very fluffy.    I am surrounded by these trees, could that  be my solution?

Been experimenting with container soil mixes for about 6 years now. The best ingredients I have found, coco coir, pine bark, perlite, sand, and broken down natural charcoal. The container type makes a big difference with what mix I intend to use.

If I am using a superoots/air prune container. I will use something close to 40% coco coir 40% pine bark 10% perlite 10% broken natural mesquite charcoal. This mix retains nice amount of water and allows ample aeration in a superoots. This mix can go without the perlite and mesquite and still perform well, however I like to add them in for a little more aeration and the surface areas which interact with microbes (especially the charcoal).

If I am using an SWC container. I will have used a variety of mixes with great results. Because the container has wick action, you can get away with high sand mixes with no perlite. I have gotten good results with 80% sand 20% pinebark. This is a simple cheap mix that will work well in an SWC. I also have found 60% pine bark, 20% coco coir, 20% perlite works as well.

For fabric containers I use a 60% Coco Coir, 30% pine bark, 10% perlite or mesquite.

Its very hard to make a bad container mix out of coco coir and pine bark. As long as none of these ingredients exceed 70% of the mix. I say forget about peat its an inferior product, unless you have the more expensive natural form bog peat moss. The acidic component of the pine bark covers whatever peat does for the PH. The coco coir is superior to peat in every way (besides the more neutral PH).

nullzero, what are you using when you first pot up a cutting?  And are they bareroot when you pot them up (don't know what propagation method(s) you're using).

I'm new to the potting mixes, but what consistency is the pine bark?  Any pictures or links I can refer to?  Thanks

I use a high content coco coir mix, since it retains water nicely and has good aeration. Coco coir with perlite 70%/30% works good. I water this mix with some low dose sea kelp powder with water, also compost tea, with a dash of azomite.

Harvey, You are opening a very big subject. The amazing thing to me is that there is an absolutely TREMENDOUS amount of high quality science available to help you make great soilless media decisions. A huge amount of work has been done & continues to be done to support the greenhouse industry. Yet, many/most people on these forums are unaware of all the information out there. Many end-up trying advice that, while very well intended, is based on anecdote with little understanding of what is really going on. Happily, most plants, and figs in particular, are pretty forgiving of broad variation in growth conditions.

It is a common theme on this forum and the gardenweb forum to blame over watering for plant deaths. Assuming you have a media whose parameters fall within the suggested ranges for horticultural use: total porosity (50% to 85%), air space (10% to 30%), container capacity (45% to 65%), available water (25% to 35%), unavailable water (25% to 35%) and bulk density (0.19 to 0.7 g/cubic cm), then overwatering should be pretty difficult. You'd almost have to try. There is a lot of concern on these forums about the perched water table. If your growth media falls within the parameters listed above, PWT will only become something that requires active management if you are growing in a VERY shallow container. Anyway, I really doubt you killed any of your potted-up cuttings due to overwatering. My guess would be that those that died were killed by pathogenic microorganisms getting into the plants via small wounds in the roots generated during the potting process. If not that, next on my list of possibilities would be media components in some of your mixes causing toxicity. In my experience, the biggest challenge in container media is not water management, but pH management. I would bet big money that far, far more plants are damaged by poor pH management than by poor water management. Attached below is a pdf discussing managing container substrates.

IMO coconut coir and coconut husk chips are terrific media components. You are talking about a very high percentage of perlite in your media, far more than should be necessary. You might also consider replacing the perlite with parboiled rice hulls. See attachments.

Tannins in fir bark should not be a problem. See attachments.

The horticulture group at North Carolina State University is really excellent. They have a TON of high-quality, authoritative information on their various web sites. I have attached a couple of their things you may find helpful.

It is too bad I did not know you were at the Santa Clara CRFG scion exchange in January. We were probably grabbing the same cuttings. Did you make it to any of the other exchanges? If so, how were the cutting selections?

Good luck with your media!

Thanks for the links.  Some I've read before but will review again.

I'm quite sure I didn't damage any of my cuttings while potting them up.  I handle them very carefully.  Each one that died was a less vigorous grower to begin with but those pots got watered pretty much the same as the others since I had so many pots to water (over 100).  A couple of days later, the leaves had wilted and I checked the pots and they were saturated and each was with a mix with low a low perlite mix.  The paper on rice hulls does not indicate the longevity of PBH and that has been a concern of mine.  Most of my plants will probably be planted into the ground this summer but it's likely some will stay in the pots until next year as back-ups.  The same paper states that trials have shown the highest growth rates in media with 20% to 30% PBH or perlite so the 25% perlite figure I've requested seems reasonable.

It would help if I knew your name to identify you.  I've gone to the SCV exchange most years (maybe missing once in the last 5 years) and I spoke there for a chapter meeting a year ago so most know me.  I also went to the Golden Gate and Sacramento exchanges the following weekend, passing up the Redwood Empire exchange this year due to schedule conflict, and attended the exchange in Mendocino.  Cuttings from Prusch get divided up between SCV, Golden Gate, Monterey, Redwood Empire, and Sacramento chapters so most have similar offerings with a few local contributions from individuals (i.e., obtained Noir de Spain mulberry at GG, a difficult to find one).

Ah - Noir de Spain , Harvey  mine came to me highly touted as best in nursery out of 15 different ones grown there on owners palate.
Time will tell.

Is it hardy enough for your location, Martin?  Or does it have a life sentence to being jailed up in a pot? ;)

Hmm kinda sound like that fella from a place he calls Paradise.  ; )
All kidding aside it is not cold hardy for my climate it has to stay in container and get
the 5 star treatment like the Dark type fig plants in yard.

so.. martin, which one would be the best? Noire de Spain or Black Beauty? are they both Morus nigra?

I have a Black Persian, Morus nigra. I was never able to taste the limited fruit it started to produce last year. It must be good because it all disappeared before it even got close to ripe. Unfortunately, I am going to sell the tree soon because its to vigorous for the limited amount of space I have.

Harvey, PBH are reported to be pretty sturdy. They compost very slowly which is why they are typically burned as opposed to composted. Note that most of the scientific papers use growth media with as few components as possible to reduce potential variables in their systems. The point I take away is that perlite and PBH are functionally equivalent. The PBH appear to be durable enough that the other components of your potting media will degrade before the PBH. You also get to avoid having to remove perlite dust before mixing and dealing with perlite getting crushed in your mix. I have not used PBH yet, but I just received a 50 lb bag. So, they are going in my next mix instead of perlite. Just to be silly, here are more PBH papers:
http://horttech.ashspublications.org/content/20/5/863.full.pdf+html
http://hortsci.ashspublications.org/content/39/2/232.full.pdf
http://horttech.ashspublications.org/content/17/3/312.full.pdf+html
http://horttech.ashspublications.org/content/18/3/384.full.pdf+html
http://horttech.ashspublications.org/content/18/4/644.full.pdf+html
http://horttech.ashspublications.org/content/18/4/650.full.pdf+html

I have no reason to doubt your diagnosis as to why you lost a few cuttings when you potted them. Saturated media is saturated media. It is worth noting that the symptoms you describe are also consistent with microorganism mediated root rot. I am only throwing it out as a possibility to add to your calculus. It is my personal opinion that it is very difficult to add potting soil on top of rooted cuttings without causing a least some micro damage to the roots. Just as minor cuts can result in life threatening infections in people, fortunately very rarely, minor damage to plant roots is also known to sometimes result in adverse effects for the plant due to infection. As I say, I am only throwing it out as another possibility for folks to consider should they encounter problems upon potting their rooted cuttings.

I just joined CRFG this past year. Thanks for the feedback on the other exchanges. I had no idea that all the groups depended on Prusch for their fig cuttings. I volunteered this year & helped mark the trees to use at Prusch for cuttings/scion with Karl Gross.  It was really cool seeing all the different cultivars in the orchard. I saw your email telling the CRFG members about Bass's stock of the Pons fig book for sale. That was a really nice, classy thing to do!

Over 100 fig trees in pots. Wow! Good luck with them!

Pete same family, send me yours and after 20 year trial i tell you which is better.  ; )

Thanks, DWD.  I saw the posting for rice hulls from the dealer in Arizona a while back and thought about it seriously but wondered if they would truly deliver here.  Where did you obtain yours from?  Perlite dust is not good and I'd love to avoid it.  It's less of a problem with the coarse stuff I bought Wednesday.  I expect my cuttings did die from rot due to either rot instigated by saturated conditions or lack of oxygen.  The mix I had used definitely did not have any air in it.

I re-pot a fair amount of plants, such as a few hundred pomegranates last summer, and those definitely get damaged easily.  The figs I have rooted appear to have quite strong roots when I pot them up and I pot them up with dry potting mix so I can be gentle in adding it.  Damage is certainly possible, but I just don't see it. The plants that died were all weaker ones planted in the media without much perlite.

Harvey, I got my PBH from a local hydroponics store as a special order. They are considering (they say) stocking it. We'll see. The manufacturer is Riceland:
http://www.riceland.com/coproducts/pbh.asp
A online source is this:
http://www.hhydro.com/PBH-Rice-Hulls.html
Be forewarned that the shipping fees are way more than the PBH which is why I went with the special order. I bit the bullet a bit, but I am so tired of screening perlite to remove dust & small bits. 

I put worm castings in the mix I pot my rooted cuttings in. The goal is to have the neutral & beneficial microorganisms provided by the worms crowd out any pathogenic microbes. The thinking is similar to encouraging patients to eat a lot of active culture yogurt after a significant course of antibiotics. You are hoping to repopulate the empty spaces with less aggressive microbes before any aggressive, overtly pathogenic ones can get established and start causing problems. One could test to see if there is a benefit in a transplant situation where you get appreciable root damage and plant death due to root rot following potting rooted cuttings. My limited experience with my figs this year is that I have not lost a plant as yet following potting the rooted cuttings. We will see what the rest of the rooting season shows.

These PBH (Par boiled rice Hulls?) sound interesting. Any chance of a small home purchaser finding them at a reasonable price locally, or is the only alternative mail-order?

DWD2, any thoughts on buying rice hulls from a feedstore and boiling them here on my farm myself?  Someone a while back posted about using rice hulls from this source on craigslist, saying they deliver throughout California as well: http://phoenix.craigslist.org/evl/grd/3659815508.html  The company with that ad has this web site with a bit more information, saying they are already sterilized somehow: http://www.permastall.com/#!rice-hull

The Craig's list link no longer is viable. The other place is a horse stall site. So... probably a local feed and seed would be a good place to start looking. Is it the boiling in water, or just heating that is desired? If it's just heat, perhaps they could be more easily solarized.