50/50 potting soil and coarse perlite (or even more perlite) would have been great for many plants. I do not use sand...what is the mix intended for?

Sand is not recommended to be part of mix unless it is quite coarse. Sure, some plants could be grown in it, but I would leave it to an experienced and knowledgeable grower. Most of us stay away from sand. I see it occasionally in potting mixes of some succulents, but always repot into much better draining mx.

Some ppl will mix C&S soil and sifted/coarse perlite in minimum 50/50 ratio. Here is a photo of that mix posted by one of our members, Crenda:

Depends what is in your ´C&S´ soil - most of them are full of acidic peat - soggy stuff which does not drain well and is unsuited to desert cacti generally. I use a coarse gritty mix which also contains crushed limestone.

Hexyl - if our plants can survive the wet summers we are in good shape. Most of my pots have the gritty mix like the second picture that Rina posted. They are all on my lanai and patio and they get rained on in the summers. It works better for me. Will yours be out in the elements or protected from daily rain?

I do still use the 50/50 mix in some of my larger pots - like these 18-inchers. I just have to be careful what I plant in there. And I don't use sand, either.

So - you've already added the sand. I would add some more perlite or grit to the mix to be on the safe side. You can get a bag of granite chicken grit at Tractor Supply for around 10 bucks. That works nice and doesn't blow away!

Ask away with any other questions!

Hexyl,

You said one of the reasons. Gritty mix never compacts, so it is much longer lasting, and can be reused when repotting. It also doesn't mold or become a home to bugs and flies. It is ideal for succulents because it dries out quickly and evenly, making it easier to control water levels.

As to plants in stores, I often see them rotting out because they have been in a 'bad' soil for too long. A heavy, peaty, organics rich soil will work out for a little while, but is definitely not ideal for long term. Most of us here intend on keeping our plants in good health for many years- much easier to do with good soil.

Yeah, that is part of it. If you want to look into the deeper aspects, here is a great post to read:

https://www.gardenweb.com/discussions/2842847/container-soils-water-movement-and-retention-xxii?n=959

A long read, but explains the logic behind using a gritty mix.

All things aside, that's a fine soil for cactus and succulents. Pot up C&S in that and they will be happy. We all have our reasons to use a more refined mix, but that one will work just fine.

Hexyl - The main reason stores and most commercial growers don't use gritty or better mixes is the cost. They have good growing conditions and can get away with cheaper mix to save money. They just need the plants to live long enough to get to your door.

I know many commercial growers and economics is important for them because it is their living. It's also very common that stores and growers really don't know what is best for their specific succulents.

Many specialty stores sell better mix components and they can be pricey. If you look at high end succulent stores, they do sell their plants in excellent soil mixes. But each plant may be in the $50-1,000+ range (CAD or USD). It's very different than from say Home Depot selling plants for $5.

Hexyl, as long as the pots are not getting soaked everyday, Rob is correct. That mix will work. But during our summers it is highly humid and it rains every day. Last summer was higher than usual, but our rain total from June thru Sept was 79 inches. My plants just didn't have a chance to dry out between rains.

Years ago, I moved my plants under the roof on the lanai for the summer where they get bright indirect sun but not the rain. That worked well enough. But I had every table and counter covered with plants and we really couldn't use the lanai! LOL So that's when I went to gritty mix. It was a sink or swim trial for the summer, and I like the results.

So your conditions and ability to care for the plants will dictate which is better for you.

How many hours of 'direct morning light' they get? Succulents - at least most of them - should get at least 6hrs of sunlight and preferably more. I don't know where you are (adding that info next to your name - as most ppl here do - helps to give more appropriate info); but depending on your location you should perhaps give them more. My plants are outside, in sunlight from sunrise 'till sunset, until it gets too cold and they have to go inside again. Don't forget to acclimatize any that would be getting better sunlight.

Rain is excellent for 'watering' plants, and while some protection maybe necessary, taking advantage of rain water is very good for plants. Having them all in very gritty and fast draining mix will help to alleviate problem of constant worrying about them getting rained on.

I grow all my plants in 100% pumice and I have had no trouble growing cuttings or leaves in pumice

Hexyl, in the picture you posted, the mix looks too sandy and it's obvious that it compacts easily. Since you are interested in the long term success of your plants, I would start over without the sand

Manuel

Hexyl posted that mix has lots of sand, exact amount is in original post.

Hexyl

Roots will colonize gritty mix very well. That is kind of substrate they grow in their habitat - inorganic, very gritty - rocky, and lean.

Hi Hexyl,

I grow indoors only & use largely 50/50 C&S mix & Pumice or (Perlite). I grow mostly succulents, Hoyas & some tropicals. They all do fine in it. We don't all use gritty mix.

I'd avoid the sand 'cause it compacts & clogs roots (if fine) & the Peat for the reasons already discussed.

The only local C&S mixes I can buy all have sand & peat in them (so since I'm growing indoor pots) I strain or sift out the finer stuff, being the sand & peat) & proceed from there, adding Perlite & Bark for my Tropicals & Pumice for my succulents. They both end up w/ excellent drainage.

Roots grow just fine in gritty mix. Here's a very small Pachypodium makayense I've been meaning to put in a slightly larger pot.

Here’s a pic of what fine sand looks like after 5-6 years. It actually starts getting compacted after only 2.

A few years ago I experimented with a mixture that looks exactly like Kara's photo. The cactus died from a combination of lack of water on my part and I'm very sure the soil, because I could hardly find any roots. There was no air in there. I think just a little bit of sand can help keep potting soil loose, but not very much at all is needed. I did use a mix with much less sand and it worked out pretty well. The peat moss wasn't caked and stuck to the roots when repotting; it came off pretty easily.

If I were to guess, Hexl's may have a little less sand and a little more perlite. If it were me, I'd do what Crenda suggested in her first comment, partly because she's grown a lot more nice plants than I have (along with everybody else on this thread).

I have always experimented with soil mixes - I think I have used about every one that has been devised during my growing lifetime - and I have found all those that were of coarse and gritty texture, thus providing excellent drainage and root aeration, consistently produced healthy and robust plants. In consequence I have always used very porous, well aerated, soil mixes for cultivating potted cacti.

In addition to producing healthy looking plants, ease of plant maintenance is an important attribute of soil mixes in my opinion. They should tolerate occasional watering misadventures and be light enough to make potted plants easily transportable. The over-riding soil attribute for me is light weight!

It is now difficult for me to produce my own growing media - the soil mix I use consists of 60% pumice (+/- ¼"/6.35mm size), 10% perlite, 30% bagged coco-peat (coconut coir).

This mix is very lightweight and provides superior drainage and optimum soil aeration. I have found it to be ideally suited for cultivating all arid land plants in our extremely dry and hot southern Arizona environment.

jp, could you let us know how you came to add the perlite at that amount? Thanks. I like to use it in addition to pumice for cost reasons.

Jeff:

Just an attempt to make the mix a liittle lighter (every gram of weight is very important to me) and because I had some to use up. i should add that pumice is free for me (courtesy of my old friend Dan Bach). I really don’t like perlite because of it’s propensity to float on the soil surface. Here is a brash statement: it is almost impossible to overwater using this soil mix (of course, that is,, here in southern Arizona) - I do not lose cacti to root rot using it despite my daily summer waterings.

Aquarium pebbles are not very good, it is too smooth and doesn't hold water or nutrients. Plus they are quite expensive compared to other good soil components.

However, it does look quite nice and makes for a good top dressing (decoration) and it can also reduce the amount of water held at the surface.

Some people DO use the aquarium pebbles because they can't find anything else, but I think they make sure that they are natural pebbles and not coated with latex (or some sort of sealant paint). Those in the picture may work, but I would find out about any paint, even if it is clear. And I think it makes a difference if the stones are granite, limestone or quartz.

I am not familiar with the size of the Quikrete gravel, but I thought it was similar in size to pea gravel of the river rock kind. I personally think that would be too big. You generally want your ingredients to be similar in size. That's why a lot of us like the crushed granite poultry grit. Tractor Supply has 25 lbs for 8.50 here. PetSmart also has it, but I don't know the cost. 25 lbs goes a long way and is cheaper in the long run over buying smaller bags that some places carry.

I've not used coir, so I really can't comment on that.

Crenda - Epoxy coated aquarium gravel is the one to avoid. Natural ones are better but still not most cost effective.

Hexyl - Sorry I have not used the Quikrete before. Poultry grit is quite cheap as Crenda mentions. It's a similar (very affordable) price here in Canada too!

Hexyl, what a refreshing thread!! You came in with questions and questioned the answers and advice - based on logic. You didn't miss anything said and as you felt something was logical, took it on board (to a point). I enjoyed the whole discussion, right from your first doubtful but intelligent responses. And what a happy ending! Keep us posted.

Very different than when I first came here. Totally overwhelmed, not able to take things in etc. I think I created a lot of frustration for those who stuck with me through that long period. And I thank them for it ;-)

I just bought some aquarium pebbles, but I only use them for top dressing on some of my plants. That's a whole different topic though. You might like this thread:

https://www.gardenweb.com/discussions/5052966/what-kind-of-mixes-and-pots-do-you-use-and-why?n=19

Amber - I envy people who can get by with amending c&s soil with good results. I see that this works well for many. However, Hexyl and I are in Florida and the soil does not dry out until October, after the rains start in June.

So it is indeed a quest! LOL My kingdom for some pumice! (I have a really small kingdom.)

We try to share ideas on how to find the stuff - or a suitable substitute - and hopefully in the most economical way possible. And in the end, like you, we use what we can find.

As ever - make the most of what you can find - we don´t all live in the US where garden centres will cater to your every desire. In my 3rd world country I can´t find dolomite lime but can get limestone chips which I bash to grit with a hammer. I can get very coarse gravel from a builder´s merchant, and volcanic rock.

But I find the most important thing for desert cacti is plenty of SUN. Sort that out before you worry about the minutiae of your soil mix. Given plenty of this most important component most desert cacti will adapt to any mix.

For my own plants I use a coarse gritty mix with limestone and just a bit of topsoil and organic nutrition.

Previously I wrote:

“i have always experimented with soil mixes - I think I have used about every one that has been devised during my growing lifetime - and I have found all those that were of coarse and gritty texture, thus providing excellent drainage and root aeration, consistently produced healthy and robust plants. In consequence I have always used very porous, well aerated, soil mixes for cultivating potted cacti.”

During my C&S growing lifetime I have cultivated my plants - sometimes in the greenhouse, sometimes outdoors depending on the location - in the following locales (approx. years):

Northern England (Lancashire) 1939 to 1950

Southern Texas 1950 to 1960

Japan (Honshu north of Tokyo) 1960 to 1963 (sporadically)

Southern California (Mohave Desert, Victorville) 1963 to 1968

Central Florida (Tampa) 1968 to 1970

Southern Arizona (Tucson) 1970 to 2018 (present)

I have always adjusted my primary soil mixes to match the growing environment/climate in accordance with the overall criterion I outline above. That is what you have to do. The soil mixes I used while growing in higher humidity environments - Northern England, Japan, Florida and to some extent Southern Texas, emphasized quick draining and mineral composition while those I used in Southern California and now here in Southern Arizona require some water retentive components (I use coconut coir for the vegetative component) because of the relentless and ferocious summer sun and extremely high temperatures. But those are just generalities - each grower has to experiment in order to meet the needs of their plants according to their environment and the availability of soil constituents.

.......... just my take on things, nothing profound or new.

JP - "I have always adjusted my primary soil mixes to match the growing environment/climate . . . "

And that is the secret to success in a nutshell.

Grace, perhaps consider using plastic pots & then you won't have the porous terra cotta 'helping' dry out your mix. Worth a try?

I have around 100 clay pots in my garage because of this. I really need to sell them off, haha!

Very informative, what about using potting soil, perlite, and silica sand 1/8"? I live in the humid part of florida and I am thinking bark would also be a good option because my orchid mix is something I think succulent soil should be similar to