I use 5:1:1 which is:

5 parts sifted pine bark mulch (chunks between 1/4 - 1/2 inch)

1 part Perlite

1 part peat moss

Garden lime 0.4 cups/5 gal mix

In your zone 9b, you should probably increase the proportion of peat moss so you wouldn't have to water so often.

5-1-1 as mentioned by Vlad is a good mix for container citrus. I use in in a lot of my container trees. Also another good mix is 50% Miracle grow garden soil and 50% Turface-MVP plus a little perlite,

I'll put in a third vote for the 5-1-1 mix! I use it it for all my containerized plants, indoor and out (except for succulents and cacti). In my zone 9a climate, I have not found a need to amend to increase moisture retention but we tend to have cool, although very dry, summers.

4th vote for the 5.1.1 mix

Hi, Kim. A equal volume of Miracle-Gro Garden Soil + Turface MVP, + a little perlite would yield nothing that even remotely resembles a productive medium for growing in containers. Even in the mind's eye it can be seen to be water-retentive in the extreme and hold very little air. This would be true of any mix based on a large fraction of garden soil, no matter the brand or what a grower might try to 'amend' it with. In order to use garden soil and have it end up being productive, it would need to be limited to something <10% of the medium, even less if the mixture contained additional fine material like peat/ coir/ compost/ composted forest products, sand.

The only way I can see it being anything even a neophyte grower would find acceptable is if it was used in a pot-in-pot, pot-in-trench, or other growing method that would ensure the lion's share of the significant amount of perched water it would contain would be forced from the pot by methods meant to overcome the physical properties of the mix which would certainly ensure a PWT of significant height. Even if MG Potting Soil for Cacti/ Succulents were to be substituted for the MG Garden Soil, it would still be excessively water-retentive and an exercise in frustration for even knowledgeable growers. Too, unless a very small fraction of Turface MVP was added to a very large fraction of coarse material (like pine bark), the Turface should be screened before use.

We can start with a list of ingredients that if combined judiciously would make a superlative grow medium, yet combine them in a manner that makes the assembled result considered unusable by most growers.

The sawdust shouldn't be used if it still smells like redwood as the phenolic compounds and terpenes it will be allelopathic to some degree; in addition, it's best if your grow medium is based on a very large fraction of coarse material. That is the principle that makes the 5:1:1 mix referred to in your post a popular choice for trees.

It might sound strange, but how you use your pot has a notable effect on how water behaves in it. To wit, a container resting directly on soil such that the grow medium in the pot is in direct contact, through the drain hole(s) and with the soil beneath the pot is hydrologically a raised bed. As such, the planting can take advantage of the earth's tendency to act as a wick or sponge, and pull excess water from the container. If, however, the pot is lifted above the soil or rests on a nonabsorbent surface (deck/concrete) and there is not an unbroken bridge between the grow medium in the pot and the absorbent earth or other material, it's simply a pot or container from the perspective of hydrology. Taking advantage of the earth's tendency to wick away excess water is a valuable tool to have in your bag of tricks. It can allow you to use some media that would otherwise be considered a poor choice in a container, but it can't work miracles and fix a medium that is innately and fatally flawed.

If you let me know about where you live, I'm pretty sure I can come up with some suggestions that will allow you to approach the task in a way that allows you to sidestep all the common pitfalls most growers run up against on their journey to a green thumb, using materials you can source locally.

Al

Al, I understand that the MG All Purpose Garden soil used by people on the Tropical Fruit Citrus forum is not your typical garden soil in that it contains bark fines which, from what I have read on that forum, is a coarse material. However, the size of the bark particles depends on where in the USA the MG Garden All Purpose Garden Soil is produced.

I have not used the 50:50 Turface garden soil mix for the reason you mention and because Turface is not as available as the ingredients of the 5:1:1 mix, which I use.

Container gardeners with goals more lofty than just being able to say they were able to keep a plant alive in a container, know, or soon learn better than to base a container medium on garden soil. I know Pam, Vladimir, Mike, and I, all contributors to this thread, learned long ago about the lack of rewards eventuating from that particular exercise in futility, as evidenced by their commentary.

I have also learned that to turn others away from information I know will detract from or limit their growing experience, it's sometimes necessary to use the extra words to clarify 'why' ideas are bound to lead to the road that should indeed remain less traveled.

As much time as I spend discussing container media with others on these fora, the closest I've ever come to learning someone is growing in a 50/50 mix of Turface and any other produce was when 'Just-a-guy', who hated perlite because it floats, started growing in a 50/50 mix of screened bark and screened Turface MVP and liked it, but that mixture would produce a medium with many times the air porosity to be found in a 50/50 mix of garden soil and presumably unscreened Turface, and he stopped participating on the forums about 15 years ago. You're not in a position you can reasonably defend, but perhaps you could coax some of the growers you know who grow in a 50/50 mix of garden soil and Turface with a little bit of perlite to share how rewarding it's been? or show us some of your containerized trees and the mix they are in. People growing in the 5:1:1 mix are already participating on this thread and I'd be more than happy to share scores of images of my trees.

Al

Many people have been quite successful with the MG garden soil (not potting soil)+ turface even though tapla says it's not possible.

"quite successful" is a very subjective assessment! How is it determined what is successful or not? And how does this match up with a plant that has been grown with a more suitable or standardized potting mix?

There is real science behind the media used for growing plants in containers so it is not just a matter of personal preferences or anecdotal reporting that should be guiding one in that direction. And yes, just about any plant can be grown in just about any media in a container for a single season. It is the long term health, viability and productivity that is in question with a garden soil ingredient as the primary component.

Kim, don't use redwood sawdust. try to find small bark (pine is fine) in like 1/4" sizes without a lot of dust fines. The problem with 5-1-1 is the 5 is small bark and that can be very difficult to source.

Oh and allow for some peat, say 10-20%

Between the 3 citrus forums, there are a lot of growers growing in Miracle Grow Garden Soil and Turface MVP 50/50. Not one single problem has ever been reported, not one, but many favorable reports are being posted. I grow both large in ground citrus trees and container trees. All of my container trees are planted in 5-1-1 except for one tree that I planted in the MGGS/T 50/50 blend. I especially planted that tree to evaluate the mixture. That tree is doing very well.

Al, most everyone would agree with you that the 5-1-1 is a good planting mix. Personally, I have 14 different varieties of containerized citrus currently growing in 5-1-1. Just because you say that MGGS/Turface 50/50 is not a proper mix to use, does not make it so, but time will certainly tell. Currently their are many growers who have switched over to growing in MGGS/Turface and are pleased with it, and have seen no difficulties. I'm not here to tell anyone what they can or cannot grow their trees in.

I think some of you are misinterpreting what is being presented here :-) It is not Al saying the 50-50 MG garden soil and turface combo is not a good mix.......it is the science that is saying that!! And that is not something that is readily refutable :-) And yes, time is one of the key factors here. As noted, of course it will work in the short term....anything will. But as the months and years progress, the collapsing and compaction of the soil (reduction in pore space/lack of aeration) will take its toll on plant roots and vitality and the plants will slowly start to decline. And the PWT will increase/rise so root rots become increasingly more likely.

But do whatever you want. I just have trouble understanding why so many are so reluctant to accept or understand this. It's almost the container gardening equivalent of anti-vaxxers, who so vehemently deny science!

That you agree or disagree doesn't matter, as I'm not here to garner your approbation. I'd rather stay the path sure to lead to a favored destination than join an averred multitude who chose a path because it offers what someone might perceive as a chance for success. I know folly when I see it, and it's helpful even if unpleasant to point to it. A wise man once said "The destroyer of weeds, thistles and thorns is a benefactor, whether he soweth grain or not".

Except to the degree I'd like to see everyone getting more from their growing experience, what they ultimately choose to grow in doesn't matter to me as I have no wish to establish the order of others' priorities. What does matter is that people have reliable information from which informed decisions can be derived. I explained in detail why what you suggested is extremely likely to be fraught with a variety of difficult problems ...... and have been listening to crickets re the heart of the matter. There's not much more I can add to the matter unless new questions arise.

Al

Funny how people have been using it for years with great results, but that isn't possible.

Lastly, this discussion brings to mind the 100+ year old centurion container citrus trees of Italy. For over 100+ years the trees have been growing in the original medium and original containers that they were originally planted in. Every 1 or 2 years 1 inch of soil is cut out manually around the sides and replaced with new medium This has been done without ever removing the trees from the container in all those years. The trees have been growing in those containers for over a century. Anyone can read about these amazing trees in Oscar Tintori's book.

I make my own version of 5-1-1 using soil conditioner and perlite. In the beginning (when I only had a few trees), I was screening the soil conditioner which left mostly bark. At 50+ trees (half in 16-20” containers), I’ll admit I’ve gotten lazy and skipped the screening. Many of these trees have plateaued in growth and production (3 years in the same medium). I need to build a large scale screen system this spring and do it right.

Nice try, i.e. completely changing the subject. Fortunately, I feel blessed I'm not compelled to attend every argument I'm invited to. I would remark though, that your argument is a logical fallacy, a non sequitur ('it does not follow'). You assume that because someone who owns or cares for old trees follows a particular care regimen, that it must be the best for all trees or all old trees, not allowing the care regimen could as well have been chosen for the simple fact that it would be much easier than a more thorough repotting process, or part of the owners' intent was to take advantage of the stress caused by root congestion to limit the growth rate and thus the size of the trees over a long term, while still maintaining the trees at not the best level, but an acceptable level of vitality. Or worse, the trees' care givers might be committing the logical fallacy called argumentum ad antiquitatem or appeal to tradition, which goes something like 'it's always been done this way, so it's the best way' or, 'if it isn't broke, don't fix it'. So while you assume the course of care you described was chosen specifically because it offered the plants optimum opportunity to realize as much of their genetic potential as possible; in fact, there are a good number of more likely reasons you have ignored or glossed over. We can know just how unlikely it is that the course of care was chosen specifically to ensure the trees' best opportunity to realize maximum genetic potential because we know with all certainty how severely limiting root congestion in the central root mass is, which also makes the original contention an error prima facie.

Would you at least agree that no wise man would count on home runs hit 100 years ago to win today's game?

Al

Al, l will just say, there is always more than one way to skin a cat. I wish the best to you and your trees.

Thank you. I hope you fare well, too.

Al

I am cheap. 2.5 cubic feet pine bark mulch, 0.5 cubic feet compost, 0.5 cubic feet Perlite.

After 4 grueling months inside. Fukushu kumquat on C35.

PG - That's pretty much the basic recipe for the 5:1:1 mix. Other than the substitution of compost for peat, and that you made no mention of having added dolomitic (garden) lime to the mix, it is the 5:1:1 mix.

Al

Just to stir the pot a little bit ;). I'm seeing elsewhere that people are having great success with coco husk chips and peat. 4 parts CHC to 1 part peat. The acidic peat presumably helps bring down the more neutral CHC. Good water retention but also incredibly light and airy, minimal PWC. Soak the CHC in Epsom salts first. I haven't tried this on a citrus tree yet but I have started testing it in some smaller houseplants. So far they seem to like it. I'm lucky in that I have a local hydroponics store that sells compressed bricks of the CHC for $12, expands to 2.5 cu. ft. Much easier for me to source and prepare than high quality bark, given what's available locally.

Most of my citrus are in a version of 5-1-1. I put my finicky Meyer in the Turface/GS mix about 2 months ago. I about gave up and repotted it two nights ago because my tree wasn't flushing like it's peers. When I got down to the root ball I saw it was dry as the desert I live in. Apparently I was checking for moisture away from the root ball and the tree is over potted. So, I'm keeping it in that mix for now and working on watering more appropriately. I don't like how heavy it is, but I do like how easy it was for me to source, and I love the way it feels. Very loamy.

I am definitely less experienced (and successful) than most of the people contributing to this thread. But I am all about trying new things and learning from mistakes.

Quite a few years back I had some interest in switching from pine bark tom CHCs, and from peat to coir. I wrote about my experience using both, and about why CHCs are not a direct substitute for pine bark and coir is not a direct substitute for peat. I'll share what I discovered and why I use neither CHCs nor coir.

Sphagnum peat and coir have nearly identical water retention curves. They both retain about 90-95% of their volume in water at saturation and release it over approximately the same curve until they both lock water up so tightly it's unavailable for plant uptake at about 30-33% saturation. While coir is easier to rewet after having dried down to <15% water retention, it has less loft than sphagnum peat, and therefore, less aeration. Because of this propensity, coir should be used in mixes at lower %s than peat. Because of the tendency to compact, in the greenhouse industry coir is primarily used in containers in sub-irrigation (bottom-watering) applications and limited to less than 10% of any medium. Many sources produce coir that is high in soluble salts, so this can also be an issue.

Using coir or CHCs as the primary component of container media virtually eliminates lime or dolomitic lime as a possible Ca source because of coir's high pH (6+). Gypsum should be used as a Ca source, which also eliminates coir's low S content. All coconut products are very high in K, very low in Ca, and have a potentially high Mn content, which can interfere with the uptake of Fe. Several studies have also shown that the significant presence of phenolic allelochemicals in fresh coir/ CHCs can be very problematic for a high % of plants, causing poor growth and reduced yields.

I haven't tested coir thoroughly, but I have done some testing of CHCs (coconut husk chips) with some loose controls in place. After very thoroughly leaching and rinsing the chips, I made a 5:1:1 soil of pine bark:peat:perlite (which I know to be very productive) and a 5:1:1 mix of CHCs:peat:perlite. I planted 6 cuttings of snapdragon, 6 cuttings of Coleus (each from the same plant to help reduce genetic influences) in containers (same size/shape) of the different soils. I added dolomitic lime to the bark soil and gypsum to the CHC soil. After the cuttings struck, I eliminated all but the three strongest in each of the 4 containers. I watered each container with a weak solution of MG 12-4-8 with STEM added at each watering, and watered on an 'as needed basis', not on a schedule. The only difference in the fertilizer regimen was the fact that I included a small amount of MgSO4 (Epsom salts) to provide MG (the dolomitic lime in the bark soil contained the MG, while the gypsum (CaSO4) in the CHC soil did not. This difference was necessary because of the high pH of CHCs and coir.) for the CHC soil.

The results were startling. In both cases, the cuttings grown in the CHC's exhibited < 1/2 the biomass at summers end as the plants in the bark mix.

I just find it very difficult for a solid case to be made (besides "It works for me") for the use of coir or CHC's. They're more expensive and more difficult to use effectively. The fact that some believe peat is in short supply (no where near true, btw) is easily offset by the effect of the carbon footprint of coir in its trek to the US from Sri Lanka or other exotic locales.

That's the view from here. YMMV

Coir Study: https://sites.google.com/site/plantandsoildigest/usu-crop-physiology-laboratory/coconut-coir-studies

Al

I have been using a mixture of coco chips, coco coir, and course perlite for years in my citrus containers. My trees are happy and reward me with many fruit each year.