webuser_355114

A Soil Discussion

tapla
November 6, 2007

A Soil Discussionsize>

Ive been thinking about what I want to say about soils here, and how I should open. IÂm going to talk a little about soils primarily from the perspective of what is best for the plant - not the planter. ;o) More often than not, the two ideas are mutually exclusive, and the plant suffers loss of vitality for grower convenience. There is absolutely nothing wrong with that. Probably none of us can afford the time it would take to give our plants the best care possible, and we need to decide on an individual basis, how much attention we can pay our plants. IÂll explain later.

Let me start by saying that whenever I say Âplants I mean a very high % of house plants and freely allow that there are exceptions to every rule; but, we need to learn the rules before we can recognize the exception. IÂm going to offer a few (of what I think are) rules I believe are difficult to challenge, and that IÂve adopted in my growing practices after a fair amount of study and consideration. IÂm going to leave light levels out of this conversation after acknowledging that they are probably just as important as soil to a planting, the difference being, we can recognize and change poor light levels easily if we choose, but poor soils are not so easily remedied.

Rule: Plants need air in the root zone as much as they need light and water. The soils we usually buy in a bag either do not supply enough aeration from the outset, or they do not supply it for a long enough period. Most, or at least many readers are expecting their plants to live in the same soil for several years, when the fact is that most peat based soils substantially collapse within a single growth cycle. That is to say that the peat particles break down into continually smaller pieces. This reduces the number of macropores (large air pockets), causes compaction, and increases the amount of water the soil holds in root zone and increases the length of time it remains there.

What does this mean to our plants? Well, there is the specter of root rot, but even if we set that aside, there is something more subtle occurring. Whenever roots are deprived of oxygen (O2) they soon begin to die - incrementally. First, and after only a few hours in saturated conditions, the finest roots that absorb water and nutrients begin to die. Already, the plant is operating under stress. Gradually, thicker roots die unless the plant uses the water in the root zone or it evaporates and O2 is allowed back into the soil. When adequate aeration is restored, the plant is disadvantaged, because fine rootage has died. The plant begins to regenerate the lost roots, but guess what? It has to call on energy reserves it has stored because the roots cannot efficiently take up water and the building blocks from which it makes food (nutrients/fertilizer). This stored photosynthate that goes to root regeneration would have been used to increase biomass - flowers, fruit, foliage, stem thickness. See how subtly aeration affects growth?

Rule: Our number one priority when establishing a planting should be to choose a soil that guarantees adequate aeration for the expected life of that planting. We can easily change every other cultural influence if we choose. Light, temperature, nutrients, moisture levels Â.. all can be changed, but we cannot change aeration, so we really need to consider that as a priority.

It is here where we need to bring attention to the fact that, as alluded to above, convenience has costs. IÂm not saying that in chiding fashion. I simply want to make the point that when youÂre able to go several days to a week without watering, in a high % of cases, the cyclic death and regeneration of roots is taking place. The plant is growing under stress and is weakened to varying degrees, depending on the severity of O2 deprivation in the root zone.

Rule: A fast soil that drains freely will be far superior from a plant vitality perspective than a more convenient soil that stays wet. The cost: YouÂll need to decide if youÂre willing to water and fertilize more frequently to secure the added vitality.

I could go on for days about soil, but IÂm hoping that IÂll be able to discuss HOW we can get to a better place with regard to our soils through answering any questions that might come up, and exploring options. Before I close, I would like to talk for a minute about another bane of poor soils.

Many of us recognize what we consider the main danger of overwatering - root rot, and do our best to prevent it. Most often, itÂs by watering sparingly so the soil is never saturated, but let me explain what happens when we do this.

Plants best take up water and the ions dissolved in it when the ion level is very low. This ion level is measured by either electrical conductivity (EC) or the total amount of dissolved solids (TDS). Problems arise when the TDS/EC level is low, when the plant can take up water easily. It remains hydrated, but starves because there is not a high enough concentration of ions in the soil water. If the level of TDS/EC is too high, the process of osmosis is affected, and the plant cannot efficiently take up either water OR nutrients, and the plant can starve or die of thirst in a sea of plenty. ItÂs up to us to supply the right mix of all the nutrients in a favorable range of TDS/EC.

IÂm sorry to be a little technical, but IÂm getting to a point. When using soils that are not fast enough to allow us to water copiously and continually flush the salts that accumulate from fertilizer and irrigation water something unwanted occurs. If we do not flush the soil, these salts accumulate. This pushes up the level of TDS/EC and makes it increasingly difficult for the plant to take up water and nutrients.

Imagine: A soil that is killing our most efficient roots, which stresses the plant and makes it more difficult to take up water due to the lack of those roots, while it insures that the level of TDS/EC will rise, making it difficult or impossible on yet another front for the plant to take up water and nutrients. Is it any wonder that our plants start to struggle so mightily toward winterÂs end? Are we really seeing the effects of low humidity or do you think it might be drought stress brought on by either an inappropriate soil or less than favorable watering practices? Probably a little or a lot of both.

Rule: Whenever you consider a plant in trouble, you must consider not only the plant, but the rest of the planting as well - including the soil. The insect infestations, diseases, and stress/strain we so often need help with here, can almost always be traced back to weakening of the organism due to an inappropriate soil (or, as noted, inadequate light - though in an extremely high % of cases, it is indeed the soil).

This only touches on the cause/effect relationship of the soil to the planting. If there are questions, IÂll try to answer them. If there is disagreement on a point or points, IÂll offer the science behind my thinking and you can decide individually if the things I set down make sense.

I would strongly urge anyone who wasnÂt long ago bored to tears to follow this link to another thread I offered on the container gardening forum. If you want to get into the science and physics of what happens to Water in Container Soils, this will help explain it. You'll also come away with the knowledge of what makes a good soil.

I hope this starts a lively discussion and provokes lots of questions, but more importantly, I hope it eventually, and as the thread progresses, helps put a few more pieces of the puzzle together for at least a few forum participants. ;o)

Please forgive grammer/spelling errors. It's late here & I'm weary. ;o)

Al

Comments (150)

  • jeannie7

    RDAK, if you've found your elixer, then by all means, stick with it. I just hope when you see a shopper buying a bag of Miracle Gro Soil or its ilk, or buying some other specialty item in that regard, then you wont feel uppity that you use the creme-de la creme and surely your plants grow better. The world is green from what they have used up to now. Maybe when man is prepared to leave this planet, more seriousness thought about what soil should go with the plants might be better thought of.

    Alenka, I said no such thing. If the reader, novice or expert, gets anything out of this technical talk, then good for that person. I doubt the average gardener gets much from it. They have soil outside they plant in. Their plant they buy in the garden centre comes with the soil they have been brought along in. Its not the thing to just up and change it.

    As far as your condemnation of peat moss, I think you doth protest too much. Peat moss keeps proving it is one of the best things to happen to plants.
    Please, if you will, state what your ill feelings about peat moss is based on. There is many an average gardener who wouldn't be without it and wouldn't make up any mix...indoor or outdoor, without its use.

  • mr_subjunctive

    Seriously, jeannie7, if you would actually read the thread on which you are commenting, you'd see that most of what you are saying is old, well-covered ground. There is a name for people who "intentionally post controversial or contrary messages in an on-line community such as an on-line discussion forum or group with the singular intention of baiting users into an argumentative response," and it is considered bad netiquette. You are welcome to start your own thread, where you give your own advice regarding soils, but please respect Al enough not to derail the conversation he has started, since there are people who are getting something out of it.

  • rdak

    I won't get uppity with someone who uses potting soil Jeannie. I'm a novice when it comes to houseplants and found Al's recipe to be excellent. That's all there is to it really.

    You know kind of like a kid who finds a new "toy". LOL!!

  • christy2828

    Whew!! Finally made it to the bottom! Thanks for all of this information, I've been looking for a new mix. It has taken me a few weeks to read, and I have an idea of what to look forward to this Spring when I repot. One quick question, what was the CRF again? I seem to have lost that part. Thanks again :) Christy

  • jeannie7

    Subjunctive, if inviting readers to stop and think, to use their own minds and decide for themselves what is proper for what this site is about, then I'm not going to just go away. Soil we put our plants into is the total of their well-being and any new idea should be examined carefully.

    If you feel such questions are argumentative....without merit, then see.....you have used your mind to make a choice.
    I invite others to do the same.

    Or would you have everybody....as though you are speaking from the pulpit....."believe in what I believe"..."do as I do"...."follow me down the path of ....

    I suggest readers to look elsewhere for their guidance about what to use for their houseplants.
    If one believes a certain source of material has meritorious "experts"....and they just keep mentioning the "off the shelf" type of potting soil, then why would one put that product down as though its had its day and the new world order is coming with new soils.

    If it gives you pleasure to think everybody that reads this material should be taken into the fold.....leave room please for us dissenters, for the less gullible and let us have a voice in challenging what the demigods would have us believe.

  • PRO
    tapla

    I was away for awhile, so I'll start back upthread at Rdak's observations about a heavy soil and whether it's organic or not (I'm smiling, btw) ;o)

    I'll just make the note that when speaking of soils, the word 'HEAVY' can mean two different things. First, it can mean the actual weight to volume ratio. The soil with the Turface and granite is fairly heavy in that way, but the mix with bark, perlite, peat, etc., is about the same weight as a bagged soil. As Rdak says though, the 'more inorganic' soil is not excessively heavy.

    The other meaning of 'HEAVY' is a soil that has lots of small particulates. Soils with lots of sand, compost, garden/top soil, worm castings, or other fine particulates are 'heavy', in that they will lack air retention. A high % of peat will eventually turn a soil 'heavy' as it breaks down. Heavy soils are characterized by slow drainage and high water retention. None of the soils I use or suggest are 'heavy' in that regard. They are always light to very light, no matter what the physical weight. ;o)
    That point is soo important, I just had to be sure it was clear. I'll always be the first to say (over and over) that when we build or buy a soil, long term aeration is key, and by far, the most important consideration, so we should consider it with every ingredient we select for a soil.

    Rdak - ;o) I keep saying one of the soil recipes, the one I always use for houseplants, is 'more inorganic' because it is made from approximately 2/3 inorganic components, materials that have never been alive - Turface & grit, but I suppose you have a point, there's nothing that would disqualify the soil from being categorized as a completely 'organic' mix. So now what do I do? You started the whole thing - I think it should be YOU that comes up with a new, better way to describe it!! Lol Put your thinking cap on? ;o) Take care.

    Puglvr - The gritty mix would be VERY good for your gardenias. When you add the Calcium source (usually you choose between garden lime or gypsum), use gypsum - it doesn't raise soil pH like lime does, and your gardenia will like a more acidic soil. You can get it in small bags at most nurseries. If you need more help with your nutrient program, just ask & I'll help you along.

    Thank you, Mr. Subjunctive & Rdak - appreciated.

    Christy - You're welcome. ;o) CRF is controlled release fertilizer, aka timed release fertilizer. Whether you add it to the mix or not isn't too important(as long as you're conscientious about supplying nutrients regularly) and is actually a seasonal thing. You prolly wouldn't want to add CRF to anything you repot or pot up after June, because of potential salt build-up.

    Al

  • jeannie7

    The use of peat moss has been arbitrarily put down as something to not use. To suggest this material has, for whatever reason, nothing to give to soil or to plants in such soil is contrary to popular belief.

    Since I'd take a chance at suggesting that millions of people the world over do use this material for what it delivers to soil, the odd one or two that is dissatisfied with the ongoing health of their plants might look elsewhere for what ails them.....its not the peat moss.

    I invite any reader who thinks about the soils they buy for all their gardening tasks to look into what peat moss is and what it can.....or cannot ...do for whatever use they might envisage.

  • christy2828

    Thanks tapla, that was easy enough! I must've missed the acronym. I have mostly succulents, just your basic jades, a few echeveria's, christmas cactus, and some Plumeria. The jades will definitely be repotted in the Spring, as well as the echeveria's. Not sure yet about the christmas cactus, and I am currently rooting the Plumeria. I'll keep an eye on this thread, thank you! Christy

  • puglvr1

    Hi AL,

    Thank you very much.I will call around tomorrow and see if I can find the gypsum. If I have any more questions, I will take you up on your generous offer and ask for help. Really appreciate it...

  • PRO
    tapla

    Make sure you ask for small bags (5 or 10 lbs) unless you want 50 lbs (most common). If you just ask for gypsum, they'll say yes & you'll be scratching your head at how many farm fields the bag will cover. ;o) Good luck!

    Al

  • rdak

    Al: "Barturfite"? LOL!!

  • m_taggart

    With regard to the popularity of using peat in potting mixes, I believe it's been used for so long and by so many people because it is relatively common and inexpensive. Consider the average gardener or houseplant owner. They probably do not spend nearly as much conversing about their plants on forums like this and just do what they've seen done; use peat based mixes. Because peat is so common, cheap, and lightweight, it makes an ideal component for premixed soils made by miracle grow and many many other companies. Less money is spent on shipping and materials when peat is used.

    On the contrary, when someone becomes a plant enthusiast they tend to gravitate toward practices that maximize plant vigor and vitality. We plant enthusiasts find a community to bounce around ideas and share what works for us. We begin to stray away from the norm and experiment with mixes that are unavailable premixed in bags. We make compost tea, grow tomatoes upside down, and engineer makeshift hydroponic systems. Sometimes someone challenges the norm and blows convention out of the water. It is up to the individual to decide whether or not this idea has merit. Anyone who has grown a plant has already looked into peat moss and what it can do for their plants. Instead, shouldn't we look into the unknown territory of turface, grit, bark, and other less conventional potting mix components and determine what they can do for our plants?

  • PRO
    tapla

    You're exactly right, M Taggert. Thanks for the kind comments! ;o)

    I didn't start this thread to try to change the mind of anyone who's resistant to change. I'll discuss the merits of soil components with anyone who has an open mind & thinks they can benefit from the discussion, and I'm perfectly happy to let people decide what's best for themselves and their plants - or if I even make sense. I think most people can see that it's my intent to show there are options and that we're not shackled to commercially prepared soils from a bag unless we want to be.

    I'm sad to see the edge of so lively an exchange of information dulled by strife, but I'm sure it's fruitless for me to argue against it, so I won't. ;o)

    I guess I should mention that I'm not just presenting some far-fetched, unproven ideas I just thought up on a whim & decided to write about. I've been using highly aerated, stable soils with either no peat at all, or less than 10-15% peat in some soils, for more than 10 years, and have studied them diligently for even longer, so it's not like I haven't paid my dues. Shoot - I've been writing about soils and helping people on these forums develop their own mixes for at least 5 years. ;o)

    Rdak - what does that mean? I'm at a loss. ;o)

    Al

  • puglvr1

    rdak,

    "Al: "Barturfite"? LOL!!"

    I think I get it, Is it your new name for the soilmix?? Short cut for the ingredients??

    1. Bark
    2. Turface
    3. Grit

  • PRO
    tapla

    Ahhh - how silly & forgetful of me! I get it now - duh! ;o) Much better than Turbarfit!

    Al

  • rdak

    Turbarfit ain't bad!!

    Pug: You're real close - bark, turface, granite. Anyway, just pulling your chains.

    Al: Plants still doing fine btw. (And this isn't the best time of season to transplant stuff. LOL!)

  • garyfla_gw

    Hi
    What a wonderful discussion!! Always found it amazing how much more difficult it is to grow a plant in a pot rather than in the ground.
    I use a lot of pots because my soil is so poor. but the pots are outside another different ballgame lol
    Always experimenting with different mixes and techniques.
    Found this post very informative even for my conditions!!!
    Think you have more than enough posts for the thread so won't add my two cents. Anyway found this very useful!!!
    gary

  • PRO
    tapla

    There are never enough, Gary. Thanks for your contribution! ;o) I'm going outside in the middle of a blizzard right now th clear the driveway before it gets so deep the snow blower won't handle it (6" so far and 6 more promised - and it's blowing/drifting). Before I go, I wanted to leave you a link to a thread similar to this one that has more than 500 posts on the same subject - Container Soils. If you're interested, it's much more technical and there are plenty of testimonials to the marked improvement hundreds (literally) of growers saw when they switched to an open and durable mix.

    Remember, I'm not trying to 'sell' MY mix here, I'm selling an open, well-aerated, and durable mix. It will eliminate or reduce multiple problems and increase the vitality with which your plants grow. ;o)

    Take care.

    Al

  • christy2828

    Planning on repotting my plants today, thought I'd top post this discussion :) Christy

  • PRO
    tapla

    Lolol! It's soo funny, Christy . . . just minutes ago, I was thinking this thread had been languishing for awhile. I had been thinking about offering a post about An EXCELLENT Fertilizer Choice, and had even gone searching for this thread. I was going to post the information I linked to, here. I didn't, because I felt that it would look like I was bumping my own thread, and I didn't want to leave that impression.

    Minutes later - YOU post to it. ;o)

    Take care!

    Al

  • christy2828

    So I think I'm ready. I've got my pine bark, my peat moss, my perlite, my lime and my CRF (Sta-Green All Purpose 19-6-12 last up to 6 months). But no micro-nutrient powder. This is what I did find, though. It's called Pogo Organics beneficial microOrganisms Essential Plant and Soil nutrients Granular. Will this work? And in what quantity? Thanks for your help, Al, and your great thread :) Christy

  • PRO
    tapla

    You may wish to look at the possibility of using a product like 'Earthjuice Microblast' as a source for the minor elements, Christy. I searched the Pogo Org. product you mentioned & found it is prepared for use in beds/gardens. It sounds like nothing more than granulated compost, which holds lots of water in containers and breaks down very quickly. Even if it was chock full of microorganisms, that is not necessarily a GOOD thing. If you have an active microorganism population in containers, they're bound to be breaking hydrocarbon chains that bind the soil particles together. This causes a rapid breakdown and premature soil collapse.

    While I agree wholeheartedly with 'feeding the soil' in gardens & beds, I think the practice is best left to those and similar places, and not carried over to container culture.

    Good luck, no matter what you decide. ;o)

    Al

  • justadncr

    Well, I have read many of the threads that talk of Al's soil and after over a year I have used a blend of bark, small amt of perlite and peat with lime, crf and micronutrients on my outside pots. I now have turface to add into this mix and have done just that with some plants I wish to leave more than a year.

    I have had very good luck even though the year was a tricky one weather wise. I can't thank Al enough for his help to me and everyone else that have benefitted from his wealth of info.

    However I am ready to go inside and repot my house plants so my search led me to this thread. I think I have reread it and have a couple questions. Sorry if I have missed the answers somewhere in the thread.

    I would like to make a great soil but as light as possible. My outside pots I don't have to lug around much. I mean I have to drag big pots inside to my sink to water and they are heavy. If I put Turface, Grit (which I have trouble finding here ) and bark it seems it would be very heavy.
    Could I use perlite bark and turface and what percentages? Grit is usually oyster shells around here. I will suffer if you really think I need grit but I would rather not use it.
    Also I use nylon rope pieces for wicks. Should they touch the ground either indoors or outside or be off the ground?

  • PRO
    tapla

    Hi, B. So nice to see you. ;o) Thank you for the kind words.

    We don't want you suffering, so how about
    5 Turface
    4 fine fir bark (or pine)
    3 perlite

    If wicks touch something absorbent, what they are touching becomes part of the wicking dynamic. If you set the containers on soil (earth), so the wick touches the soil or grass, the earth becomes a giant wick. If the wick dangles a couple of inches from the bottom of the container so water drips off & more can follow down the wick, it's equally effective. Wicks become ineffective when the water cannot drain away from the wick - such as when you set a container on a patio slab and a puddle forms around the bottom of the container with the wick contacting the water in the puddle. That cover it?

    Asides: If you suspect your containers are retaining perched water, you can at least partially remedy the condition by tilting the container at a steep angle after watering. Test this by watering (saturating) a container thoroughly. After the container stops draining (it reaches container capacity) tilt it and note how much additional water exits the container. Of course, a wick is still much more effective, but this will assist those not using wicks and help with soggy soil.

    Remember - many of your plant problems arise from using heavy soils that you must water in sips to prevent root rot. If you rid yourself of these soils so you can water copiously (as B has done), MANY of your issues (including insect troubles, diseases, root rot, and other problems associated with over-watering and soluble salts accumulation) will go away. This is ESPECIALLY important in the winter.

    Al

  • justadncr

    Thank you for the advice. I will use that formula. Do I put micromax in the mix and leave out CRF?

    So if I drain my plants well in the house I can put them back into trays on the floor?
    I do water them as you suggest. ie water til it all drains out, wait a few minutes then water with a weak fert (24 8 12) as recommended then I always tilt them for a few minutes before I put them back.

    When I first read all of this about a yr and a half ago I was so excited. I went out an purchased bark and perlite but if you remember Al I used mushroom compost instead of peat. I realized after talking to you that was far from ideal but actually the plants have done much better than the soil I have used in the past. However I am excited since I now have Turface!
    The mushroom compost has of course broken down.

    Another trick I love that you taught me was to put old screen in the bottom of outside pots to keep the bugs out!

    Thanks again for your advice Al and all the others who really make this site so beneficial

  • PRO
    tapla

    I would forget the CRFs in houseplants or in any plant you will need to over-winter before the fertilizer in the capsules is depleted. In my experience, CRFs in over-wintering plants cause sometimes extreme accumulations of soluble salts, which can be disaster in slow soils. If you're using the MG 24-8-16, 12-4-8, or other incomplete (lacking secondary macro or micronutrients) fertilizer, use your Micromax. If you're using a complete fertilizer, like Foliage-Pro 9-3-6, you can skip it.

    If you use the MG, you'll be lacking Ca and Mg, so you'll need to supply it with gypsum (added to the soil) and Epsom salts (added to fertilizer water when you fertilize).

    "So if I drain my plants well in the house I can put them back into trays on the floor?"

    Oh sure.

    "I do water them as you suggest. ie water til it all drains out, wait a few minutes then water with a weak fert (24 8 12) as recommended then I always tilt them for a few minutes before I put them back."

    It's best to water so copiously that 10-15% of the total volume of water applied exits the drain each time you water. It's not absolutely necessary to water this way to maintain peak vitality, but you should do it at least every third or fourth time you water, and flush more thoroughly than if you do it every time you water.

    It's often parroted that you shouldn't water a dry plant or a 'sick' plant. The 'sick' plant part makes no sense, but it's beyond what you asked, so I'll leave it be. The "Don't water dry plants" mantra is more a safeguard to protect plants in slow soils that are likely to have high accumulations of salts in the soil, but we should talk about what 'dry' is. Plants that are too dry to fertilize will be under some drought stress - even cacti and succulents. If the plants leaf structure is such that you couldn't detect wilting if the plant was drought-stressed, it's better to be sure there is some soil moisture when you fertilize. If you are talking about foliage plants that visibly wilt, if there are no signs of wilt - even if the soil FEELS dry - it's ok to fertilize. It's especially harmless in your case because you're using a fast soil that allows you to flush salts out, and you're using a dilute fertilizer concentration. With fast soils and proper watering technique, along with dilute fertilizers, you can fertilize at EVERY watering if you choose - even in winter.

    I do fertilize my houseplants all year long - even in winter. It does no harm to make nutrients available at reasonable levels at all stages of the growth cycle - even if plants are not growing. It's not totally necessary, but it does no harm, either. When my houseplants are outdoors in the summer & growing robustly, I usually fertilize weekly at 1/2 strength. When temperatures drop below 50* or rise above 85*, I slow applications dramatically until temps return to favorable growth levels. When plants are resting (indoors), I fertilize at around 1/8 recommended strength at every watering (winter).

    "When I first read all of this about a yr and a half ago I was so excited. I went out an purchased bark and perlite but if you remember Al I used mushroom compost instead of peat. I realized after talking to you that was far from ideal but actually the plants have done much better than the soil I have used in the past. However I am excited since I now have Turface! The mushroom compost has, of course, broken down."

    Yes, compost, and especially mushroom compost can be very problematic in container soils. The compost in general because of its small particle size and water retention, and the mushroom compost for the same reason, plus the fact that it usually comes to you very hot (high in N - lots of urea) and very high in soluble salts. I think you'll be even more excited when you've removed the compost from your mix. I think you're about to see another big improvement in the results of your growing efforts - at least I HOPE so! ;o)

    Take good care, B.

    YPA


  • justadncr

    I see. The Peters professional water soluble with micronutrients doesnt have MG or Ca in it. I do usually put dolomite lime in my outside plant mix. About how much lime would I put in a 5 gallon bucket worth of mix for houseplants? Thanks again.
    Darn I cant find the thread where I asked all these same questions last year but I have reviewed alot. I have been through alot of threads! Also maybe I will be helping someone else. Thanks again!

  • PRO
    tapla

    Don't worry about repeat questions, B.

    Instead of lime, use gypsum (1 tbsp/gallon of soil). The pH of the gritty soil mix should come in at just under 6.0 before liming, which is almost perfect because media pH tends to rise as it ages. Lime supplies both Ca and Mg, but it raises media pH. Gypsum supplies Ca and S, without raising pH; that's why I use gypsum as a Ca source in the gritty mix and then supplement the Mg by adding 1/4 tsp Epsom salts to the fertilizer water every time I fertilize. This regimen has worked very well for me over the years when growing in the gritty mix.

    If you were using the 5:1:1 bark:peat:perlite mix, I would stay with the dolomitic lime @ the same rate - 1 tbsp/gal soil.

    YPA

  • justadncr

    Wow I can't believe I didn't have gypsum and went to the local store and they had it!! I'm set now . I did mix some up and it looked to me like I needed more turface so I did 6 turface 4 bark chips (I used soil conditioner) and 3 perlite. So i don't have to use Micromax if I have the fert with micronutrients and use it weakly weekly? Anything else? Thanks YPB

  • PRO
    tapla

    Just good luck ;o) - and I'm glad you're back safe and had such a great time! ;o)

    YPA

  • gary30mazak

    I am growing several palm trees and a sago in containers. Do you have a good soil recipe for palm trees?

  • PRO
    tapla

    A soil that has been very well received for growing succulents and palms is:

    3 parts fine pine or fir bark
    3 parts Turface MVP
    3 parts crushed granite
    1 part coarse sand (very coarse - at least 1/16" diam. Find at store that sell swimming pool filter sand or ask for very coarse silica @ masonry supply stores)
    1 part vermiculite
    Dolomitic (garden lime) or gypsum

    You can see a picture of this soil if you scroll upthread to the first set of pictures (10, altogether) you come to. The bottom pic is the soil. It is very porous and will not hold excess water. It drains extremely well, and most importantly, it will allow you to water copiously at every watering w/o risking the water retention, during periods of low water demand, that rots roots.

    You can make it simpler by using a 1:1:1 mix of bark fines:Turface MVP:crushed granite if you don't care to look for too many ingredients. I have found this soil to be excellent for everything I've tried in it. I have ALL my houseplants in it, and grow all my woody plants in the simpler 1:1:1 mix.

    Several from this forum have tried it or a slight variation, and many from the container gardening forum - perhaps someone will offer up their own assessment(s). I just finished a small batch for a friend before an IPM meeting I attended earlier tonight.

    Take care.

    Al

  • zubababy

    Al,

    I would like to thank you for all the information you have put into these forums.

    Many times I see posts where someone says to add perlite to regular soil for a newbie, because they dont want to frustrate or make it hard for a newbie to take care of their plant. I dont have much experience in growing plants and I have tried the perlite route and many other amendments that I have seen mentioned on these forums. Some worked ok, but I have had the most success with your 1-1-1 mix. I still have yet to find granite grit here. I have replaced the crushed granite with small gravel that is marked as paver base. It seems to be working very well.

    I have a heavy hand when it comes to watering, and this mix is the only one I have found that works for me, and my plants are growing great. I have had a few plants on deaths door that has been revived after putting in the 1-1-1 mix.
    I also like that I dont have to be as careful about selecting too big of a pot when I use this mix.

    I got a meyer lemon tree this spring, and repotted into your mix. I used a large container for it and it is thriving. It is starting to put on lots of new growth.

    I almost have everything transferred to this soil. Just a few more plant to change.

    I try to read as many posts as I can where you have responded, and I appreciate that you take the time to help everyone out, and explain most things in an easy to read and understand format.

    I just wanted to include a pic of some roots from a succulent that I have growing in this mix. I water every 1-2 days, and its roots are amazing. You can even see the tiny root hairs on it. I havent seen roots like this on anything that I have purchased.

    {{gwi:55329}}

    Here is a pic of my lemon tree with lots of new growth in an oversized container.

    {{gwi:110498}}


    {{gwi:110499}}

    Thank you for helping this newbie to grow like a pro :)

  • PRO
    tapla

    Ohh, thank you, Zuba. I really wasn't soliciting thank yous, just the honest assessments of those who had used any of the soils I like to share, but I sure want to thank you for the effort and very kind words. It's certainly appreciated. I'm glad you feel like you're having an improved growing experience. Soils are soo much more important than most realize - the foundation that every planting is built on.

    If you like succulents, I have a couple you might be interested in, if you contact me off forum.

    Take good care.

    Al

  • gary30mazak

    I appreciate you responses greatly. I just started growing palms this past spring and although all have survived they are not thriving like I know they can. I am currently using a miracle-go perlite mix and it seems too thick and heavy even to an amature. Last week I bought some Natures Best soil conditioner from HD and am currently looking for Turface and the Granite. Anyone know where to get these items in Charlotte NC? I will hit the farm and golf course stores tommorrow. Also will the 1-1-1 mix hold up for over a year or would I need to repot annually? I hate repotting because I always lose a frond or two from shock I guess and it kills me to see my palms suffer. anyway thanks again for all your advice. Garry

  • PRO
    tapla

    For Turface, try Burnett Athletics in Charlotte first. (864) 592-1658 The granite might be harder to come by because you guys usually use crushed shellfish shells for grit, but I'd try rural feed stores & elevators - places that cater to farmers & have farm animal feed.

    The 1:1:1 mix is 2/3 inorganic and 1/3 very stable bark, so it will last longer than it is prudent to allow a planting to go w/o repotting. IOW - it's extremely stable and will remain serviceable for 5-10X longer than a bagged peat-based soil and about 2-3 times as long as the bark based soil I mentioned upthread, and there's no way you should expect a plant (well, a huge % of plants) to go that long between repots.

    Take care. Best of luck.

    Al

  • jodik_gw

    I don't usually frequent the Houseplant Forum, but I do grow many types of plants indoors, so I guess they are, by logistics, "house plants". My indoor collections include a large number of Hippeastrum bulbs, several orchids, and a few other tender or tropical type plants.

    For quite a while, I struggled with finding the right medium for my bulbs... I was experiencing root rot and bulb rot constantly! I tried everything from expensive bagged soils to coco coir, and everything in between! It wasn't until I "met" Al, and read what he had to convey, that I understood what I was doing wrong! I was literally suffocating my plants from the roots up!

    I have since switched to Al's Mix for many of my plants and bulbs... and every one that's planted in a larger particled, free-draining mix is growing phenominally! I can't say enough about the types of mixes Al talks about!

    I recently un-potted a container of Sprekelia to separate them, and upon hosing off the mix, saw the most beautiful, healthy root system I've ever grown on a bulb! They were long and thick and white, and extremely healthy!

    For years, I've been using layers of gravel or charcoal at the bottom of my pots, thinking that this is aiding in drainage... it's not. But now that I understand perched water tables and proper watering techniques, and am using a soil that allows for the exchange of oxygen and gases, I see that using a mix like Al's from top to bottom in a clay pot is the answer.

    I doubt I've covered all the reasons that a larger particled free-draining bonsai like medium is better, but I don't have the time right now... I'm on my way outdoors to take care of my container gardens!

    Happy Gardening... and for everyone growing in any type of container... please read what Al has written about Soils, Perched Water Tables, Water Retention and everything else... you won't be sorry!

  • gary30mazak

    Well I found the turface on the 1st try Lescos about 3 miles from my house had turface allsport same as MVP for $9.75 for a 50# bag. The crushed granite I'm going to have to search a little more for. I couldnt find it anywhere. But I bought a small bag of aquarium gravel to hold me over till I cand find some crushed granite and I,m going to try the 1-1-1 mix on a diffenbachia that I have that has really gone downhill lately. I fed it diluted coffee after reading that they like that and I have just about killed it. It needs a transplant bad. I also picked up a CRF called dynamite select 15-5-9 with micros. I couldnt find the scotts/ peters excel 15-5-15 fert. Would palms like this and could i add a little potash to the mix to raise the K2o up to 15? also should I let my soil conditioner dry before mixing with the turface? Also if anyone knows a good source for crushed granite in the Charlotte NC area please let me know! Another question do I need to add lime to the 1-1-1 mix and if so how much? I can only make about 2 gallons at a time since I live in a apartment. Thanks again and sorry to pester ya,ll with my dumb questions. Please be paitent I'm new to this.

  • gary30mazak

    Another question. How small should the crushed granite be. I found a few sources near me but its not granite and I can get 3/8 inch whitestone and gravel screenings which look too fine to me. would 3/8 be too big and can it be any kind of rock?

  • PRO
    tapla

    Thanks, Jodi. That was very nicely said. It makes me feel good - glad to see testimony like yours, but not because I get a personal boost from it. I think it helps to convince people that some deviation from the bagged mixes we so often offer our plants can be a very good and worthwhile thing. Comments like yours and Zubababy's (I don't know if I should use a real name) might help a few who are hesitant to try a different way of looking at soil. That's what I hope for and that's what, out of the whole deal, makes me feel good. ;o) Anyway - thanks again.

    Eileen from NYC:size> If you're still following the thread, will you please contact me off forum? I remember helping you find the ingredients for the 1:1:1 gritty mix a while back, and I'm wondering if you can help me now. I have a friend from NYC that is asking, and I didn't write down (and I sure as heck can't remember) where to find the ingredients. Thank you. ;o)

    Gary - you don't need to feel like you're 'pestering' me. I have all the patience in the world for people with good faith questions. I always try to answer in the best way I can.

    There's a lot of conversation on the forum lately about adding dilute coffee/tea to plants. I replied on one thread & got beat up pretty bad for offering the reply, but Arabica (coffee) and Camellia (tea) are known for their toxic alkaloid (caffeine) content and their allelopathic affect on plants as well as autotoxic (to their own seedlings) effects on future generations. Caffeine interferes with root development by impairing protein metabolism. This affects activity of an important bio-compound (PPO) and lignification (the process of becoming woody), crucial steps for root formation.

    We also know that the tannins in both coffee and tea are known allelopaths (growth inhibitors). There are ongoing experiments to develop herbicides using extracts from both coffee and tea that cause me to want to say they might serve better as a nonselective herbicide than as a tonic. I would not use either on my plants.

    I think a 2:1:3 ratio (or close) like 8-4-12, or even the 15-5-15 you suggested, would be very good for palms. I don't often use the CRFs because I like complete control over 'when and how much', but I think I would probably do as you suggest if I was using it and add a tsp (or a little more) of potash to each gallon of soil.

    You lost me on the ... should I let my soil conditioner dry before mixing with the Turface? Do you have wet bark & you're asking how dry it should be when you make the soil? It's ok if it's wet, but it shouldn't be wringing wet. You shouldn't be able to squeeze any water out of a handful if you squeeze it hard.

    Lime (Mg and Ca) is very important to palms, so add a tbsp per gallon of soil. Make sure your fertilizer is supplying Mn, too. It's important. I think I would add a micronutrient supplement like Earth Juice's MicroBlast. It has Mg and the minors that are apt to be missing in container soils. Interestingly, it has no Ca or S, which is convenient. If you use the MicroBlast, just switch the lime (Ca & Mg) to gypsum (calcium sulfate) which nicely covers your Ca/S problem. ;o)

    Did you get all that? ;o) If you didn't understand something, let's get it cleared up. I'm heading out to water containers. It's hot & muggy (for us, anyway) here 90*/86% humidity. Yuk.

    Al

  • PRO
    tapla

    I just noticed your other post. I also forgot to say "Way to go!" for finding your Turface.

    You want the particle size of the granite to be in the 1/16 - 3/16 range with almost all the particles in the 1/16 - 1/8 size. The beauty of the Grani-Grit is that it comes pre-screened in 'starter' and 'grower' sizes and is very uniform. I never tried this tack before, but I'm going to look at my bags of grit & see if I can contact the mfg & find out who sells it where. I should have tried this long ago.

    If you can't find it, try very coarse (1/16+) silica sand from a pool supply place (used in filters) or inquire at a masonry supply store (not big box) for the coarsest silica they can get (1/16-1/8 is best). If you STILL strike out, come back & we'll figure out how to make a mix w/perlite instead.

    Take care.

    Al

  • jodik_gw

    Al - I'm beginning to see how many bagged medium mixes are just like many other products on the market... especially pet foods... they're aimed at sales to people, not at the health of plants! It's all a money game at the base line!

    I know you're not looking for personal glory by helping us learn to grow better plants, but it's perfectly alright to take a little for yourself! You've done, and continue to do, a great service for us gardeners! You've done all the math, science and history for us, and broken it all down into easy-to-understand terms! You certainly deserve a pat on the back, at the very least! Where can I sign you up for "Garden Mentor Of The Year"?!

    As I said, I've been gardening for decades... and after reading only one of your articles, I can finally say: I get it! I finally get it! And my plants today reflect that!

    Thank me for saying so? No... thank YOU... for being such a patient and sharing teacher!

  • arjadiejai

    Whew, so I finally got through reading this whole thread, there certainly is a plethora of good and interesting info in there!

    Here are a couple of questions that occurred to me as I was reading:
    Have you tried rooting cuttings in this mix? Due to how fast it drains, it sounds like it might work well (depending on the plant, I suppose). About the cacti and succulents, if you water your âtypicalâ tropical houseplants every day or every other dayâ¦how often would you water the cacs & sucs in comparison?

    Also, have you ever ventured into terrariums? Would you use a mix of this sort in there?

    Thanks so much for sharing your knowledge with us!

  • PRO
    tapla

    Again, I don't know what to say, Jodi. My face got all red (yeah, I blushed) and I was really touched by your comments. I'm just really glad you're getting more out of your growing experience. THAT really rocks me. ;o)

    From Arjadiejai:

    Have you tried rooting cuttings in this mix?

    If I have a cutting that is important to me, or hard to root, I always stick it in a sterile medium like perlite or Turface. Strangely, I get the VERY best results from rooting in chopped sphagnum moss (not peat - the whole pieces of moss that were harvested live). The moss makes sense if you consider it's the medium most used in air layering. A mix of any combination of the three ingredients also works very well.

    If I'm starting cuttings and I really don't care about the strike rate, I use a soil made of screened Turface, fir bark, and crushed granite - the same soil as above. I screen it so particles are all larger than 1/16 inch so there is almost NO perched water to rot cuttings. By doing it that way, I can start the cuttings in larger containers and not have to worry either about a setback from potting up soon after the cuttings strike, or about overpotting and the accompanying saturated soil. In short, cuttings root fast and you can save a step because of a larger soil volume, but again - if the cuttings are important, use a sterile medium - it's the bark that could harbor rot organisms.

    About the cacti and succulents, if you water your typical tropical houseplants every day or every other day, how often would you water the cacs & sucs in comparison?

    It varies. I have caudex forming succulents that get water once/week in winter (they're under lights in winter), and every other day in summer (outdoors/full sun/clay pots). The plants in plastic pots get watered less & the ones in clay pots get it more - you know how that goes ..... I/you just develop a feel for what is needed & when after a while I guess. I kind of have a calculator in my mind that factors in how hot it's been, how windy, how much sun, how big the plant is in relation to the pot size and soil volume ..... and I decide based on that. With succulents & cacti, if I'm in doubt, I usually wait.

    To answer your question directly: It varies, but the interval between waterings is about twice as long - all things being equal.

    Also, have you ever ventured into terrariums? Would you use a mix of this sort in there?

    I haven't done terrariums, but I worked with a guy to develop a soil and fertilizer program for his. I think he was doing them to sell, and I might even have sent him some soil to try, I don't remember - I talk to a lot of people off forum about plant stuff. I didn't save his e-mail addy, but I talked quite a bit with him on a thread over on the Container Forum. I might go over there & see if I can look him up & find how he fared, but only if you're interested. ;o)

    Al

  • PRO
    tapla

    Again, I don't know what to say, Jodi. My face got all red (yeah, I blushed) and I was really touched by your comments. I'm just really glad you're getting more out of your growing experience. THAT really rocks me. ;o)

    From Arjadiejai:

    Have you tried rooting cuttings in this mix?

    If I have a cutting that is important to me, or hard to root, I always stick it in a sterile medium like perlite or Turface. Strangely, I get the VERY best results from rooting in chopped sphagnum moss (not peat - the whole pieces of moss that were harvested live). The moss makes sense if you consider it's the medium most used in air layering. A mix of any combination of the three ingredients also works very well.

    If I'm starting cuttings and I really don't care about the strike rate, I use a soil made of screened Turface, fir bark, and crushed granite - the same soil as above. I screen it so particles are all larger than 1/16 inch so there is almost NO perched water to rot cuttings. By doing it that way, I can start the cuttings in larger containers and not have to worry either about a setback from potting up soon after the cuttings strike, or about overpotting and the accompanying saturated soil. In short, cuttings root fast and you can save a step because of a larger soil volume, but again - if the cuttings are important, use a sterile medium - it's the bark that could harbor rot organisms.

    About the cacti and succulents, if you water your typical tropical houseplants every day or every other day, how often would you water the cacs & sucs in comparison?

    It varies. I have caudex forming succulents that get water once/week in winter (they're under lights in winter), and every other day in summer (outdoors/full sun/clay pots). The plants in plastic pots get watered less & the ones in clay pots get it more - you know how that goes ..... I/you just develop a feel for what is needed & when after a while I guess. I kind of have a calculator in my mind that factors in how hot it's been, how windy, how much sun, how big the plant is in relation to the pot size and soil volume ..... and I decide based on that. With succulents & cacti, if I'm in doubt, I usually wait.

    To answer your question directly: It varies, but the interval between waterings is about twice as long - all things being equal.

    Also, have you ever ventured into terrariums? Would you use a mix of this sort in there?

    I haven't done terrariums, but I worked with a guy to develop a soil and fertilizer program for his. I think he was doing them to sell, and I might even have sent him some soil to try, I don't remember - I talk to a lot of people off forum about plant stuff. I didn't save his e-mail addy, but I talked quite a bit with him on a thread over on the Container Forum. I might go over there & see if I can look him up & find how he fared, but only if you're interested. ;o)

    Al

  • jodik_gw

    My finest accomplishment since becoming one of Al's "groupies" is seeing the fresh, new growth of leaves on my very young Clivia miniata! I was gifted with a small Clivia offset by a dear friend, and since these are rather expensive plants, I wanted very much to see it live and grow!

    I potted it up in clay using Al's Mix, set it on a shaded south windowsill where it gets no direct sun, and waited impatiently for it to do something... I half expected it to die, truth be told... it stayed green, and although it took quite a while, new leaves are growing!

    I'm very diligent about checking the pot for moisture, and I think I must be doing ok... fresh new leaves signal good health!

    All I have to do now, is find out how and where to get dump truck loads of Al's Mix ingredients in my neck of the woods, and a giant mixer, so I can pot everything in it! LOL!

  • gary30mazak

    Well I found my Gran-I-Grit. I had to special order it from Southern States Coo OP. $7.69 for a 50# bag. Not too bad. It should be here wendsday but I probably wont be able to pick it up till saturday. I got the growers blend which I hope is the right size.

  • PRO
    tapla

    Strong work!! It will be fine - 'Grower' size is what I use most often. ;o)

    Al

  • PRO
    tapla

    Since the thread is about to end at 150 posts, please follow the link to the continuation if interested.

    A Soil Discussion II

    Thanks to those who followed the thread, and especially to those who participated in good faith. ;o)

    Al

  • jillalamedat

    If you're still out there, I have a question. Please forgive me if it's answered above; there are well over 100 posts and I only read through the first 20 or 30.

    Would adding decomposed granite improve bagged potting mix? If so, what proportion would you recommend?

Need help with an existing Houzz order? Call 1-800-368-4268