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Container Soils - Water Movement & Retention XIV

tapla
11 years ago

I first posted this thread back in March of '05. Thirteen times it has reached the maximum number of posts GW allows to a single thread, which is much more attention than I ever imagined it would garner. I have reposted it, in no small part because it has been great fun, and a wonderful catalyst in the forging of new friendships and in increasing my list of acquaintances with similar growing interests. The forum and email exchanges that stem so often from the subject are, in themselves, enough to make me hope the subject continues to pique interest, and the exchanges provide helpful information. Most of the motivation for posting this thread another time comes from the reinforcement of hundreds of participants over the years that the idea some of the information provided in good-spirited collective exchange has made a significant difference in the quality of their growing experience.

I'll provide links to some of the more recent of the previous dozen threads and nearly 2,000 posts at the end of what I have written - just in case you have interest in reviewing them. Thank you for taking the time to examine this topic - I hope that any/all who read it take at least something interesting and helpful from it. I know it's long; my hope is that you find it worth the read.

Container Soils - Water Movement and Retentioncolor>size>

A Discussion About Container Soilscolor>size>

As container gardeners, our first priority should be to ensure the soils we use are adequately aerated for the life of the planting, or in the case of perennial material (trees, shrubs, garden perennials), from repot to repot. Soil aeration/drainage is the most important consideration in any container planting. Soils are the foundation that all container plantings are built on, and aeration is the very cornerstone of that foundation. Since aeration and drainage are inversely linked to soil particle size, it makes good sense to try to find and use soils or primary components with particles larger than peat/compost/coir. Durability and stability of soil components so they contribute to the retention of soil structure for extended periods is also extremely important. Pine and some other types of conifer bark fit the bill nicely, but I'll talk more about various components later.

What I will write also hits pretty hard against the futility in using a drainage layer of coarse materials in attempt to improve drainage. It just doesn't work. All it does is reduce the total volume of soil available for root colonization. A wick can be employed to remove water from the saturated layer of soil at the container bottom, but a drainage layer is not effective. A wick can be made to work in reverse of the self-watering pots widely being discussed on this forum now.

Since there are many questions about soils appropriate for use in containers, I'll post basic mix recipes later, in case any would like to try the soil. It will follow the Water Movement information.

Consider this if you will:

Container soils are all about structure, and particle size plays the primary role in determining whether a soil is suited or unsuited to the application. Soil fills only a few needs in container culture. Among them are: Anchorage - a place for roots to extend, securing the plant and preventing it from toppling. Nutrient Retention - it must retain a nutrient supply in available form sufficient to sustain plant systems. Gas Exchange - it must be amply porous to allow air to move through the root system and gasses that are the by-product of decomposition to escape. Water - it must retain water enough in liquid and/or vapor form to sustain plants between waterings. Air - it must contain a volume of air sufficient to ensure that root function/metabolism/growth is not impaired. This is extremely important and the primary reason that heavy, water-retentive soils are so limiting in their affect. Most plants can be grown without soil as long as we can provide air, nutrients, and water, (witness hydroponics). Here, I will concentrate primarily on the movement and retention of water in container soil(s).

There are two forces that cause water to move through soil - one is gravity, the other capillary action. Gravity needs little explanation, but for this writing I would like to note: Gravitational flow potential (GFP) is greater for water at the top of the container than it is for water at the bottom. I'll return to that later.

Capillarity is a function of the natural forces of adhesion and cohesion. Adhesion is water's tendency to stick to solid objects like soil particles and the sides of the pot. Cohesion is the tendency for water to stick to itself. Cohesion is why we often find water in droplet form - because cohesion is at times stronger than adhesion; in other words, water's bond to itself can be stronger than the bond to the object it might be in contact with; cohesion is what makes water form drops. Capillary action is in evidence when we dip a paper towel in water. The water will soak into the towel and rise several inches above the surface of the water. It will not drain back into the source, and it will stop rising when the GFP equals the capillary attraction of the fibers in the paper.

There will be a naturally occurring "perched water table" (PWT) in containers when soil particulate size is under about .100 (just under 1/8) inch. Perched water is water that occupies a layer of soil at the bottom of containers or above coarse drainage layers that tends to remain saturated & will not drain from the portion of the pot it occupies. It can evaporate or be used by the plant, but physical forces will not allow it to drain. It is there because the capillary pull of the soil at some point will surpass the GFP; therefore, the water does not drain, it is said to be 'perched'. The smaller the size of the particles in a soil, the greater the height of the PWT. Perched water can be tightly held in heavy (comprised of small particles) soils where it perches (think of a bird on a perch) just above the container bottom where it will not drain; or, it can perch in a layer of heavy soil on top of a coarse drainage layer, where it will not drain.

Imagine that we have five cylinders of varying heights, shapes, and diameters, each with drain holes. If we fill them all with the same soil mix, then saturate the soil, the PWT will be exactly the same height in each container. This saturated area of the container is where roots initially seldom penetrate & where root problems frequently begin due to a lack of aeration and the production of noxious gasses. Water and nutrient uptake are also compromised by lack of air in the root zone. Keeping in mind the fact that the PWT height is dependent on soil particle size and has nothing to do with height or shape of the container, we can draw the conclusion that: If using a soil that supports perched water, tall growing containers will always have a higher percentage of unsaturated soil than squat containers when using the same soil mix. The reason: The level of the PWT will be the same in each container, with the taller container providing more usable, air holding soil above the PWT. From this, we could make a good case that taller containers are easier to grow in.

A given volume of large soil particles has less overall surface area when compared to the same volume of small particles and therefore less overall adhesive attraction to water. So, in soils with large particles, GFP more readily overcomes capillary attraction. They simply drain better and hold more air. We all know this, but the reason, often unclear, is that the height of the PWT is lower in coarse soils than in fine soils. The key to good drainage is size and uniformity of soil particles. Mixing large particles with small is often very ineffective because the smaller particles fit between the large, increasing surface area which increases the capillary attraction and thus the water holding potential. An illustrative question: How much perlite do we need to add to pudding to make it drain well?

I already stated I hold as true that the grower's soil choice when establishing a planting for the long term is the most important decision he/she will make. There is no question that the roots are the heart of the plant, and plant vitality is inextricably linked in a hard lock-up with root vitality. In order to get the best from your plants, you absolutely must have happy roots.

If you start with a water-retentive medium, you cannot improve it's aeration or drainage characteristics by adding larger particulates. Sand, perlite, Turface, calcined DE ...... none of them will work. To visualize why sand and perlite can't change drainage/aeration, think of how well a pot full of BBs would drain (perlite), then think of how poorly a pot full of pudding would drain (bagged soil). Even mixing the pudding and perlite/BBs together 1:1 in a third pot yields a mix that retains the drainage characteristics and PWT height of the pudding. It's only after the perlite become the largest fraction of the mix (60-75%) that drainage & PWT height begins to improve. At that point, you're growing in perlite amended with a little potting soil.

You cannot add coarse material to fine material and improve drainage or the ht of the PWT. Use the same example as above & replace the pudding with play sand or peat moss or a peat-based potting soil - same results. The benefit in adding perlite to heavy soils doesn't come from the fact that they drain better. The fine peat or pudding particles simply 'fill in' around the perlite, so drainage & the ht of the PWT remains the same. All perlite does in heavy soils is occupy space that would otherwise be full of water. Perlite simply reduces the amount of water a soil is capable of holding because it is not internally porous. IOW - all it does is take up space. That can be a considerable benefit, but it makes more sense to approach the problem from an angle that also allows us to increase the aeration AND durability of the soil. That is where Pine bark comes in, and I will get to that soon.

If you want to profit from a soil that offers superior drainage and aeration, you need to start with an ingredient as the basis for your soils that already HAVE those properties, by ensuring that the soil is primarily comprised of particles much larger than those in peat/compost/coir.sand/topsoil, which is why the recipes I suggest as starting points all direct readers to START with the foremost fraction of the soil being large particles, to ensure excellent aeration. From there, if you choose, you can add an appropriate volume of finer particles to increase water retention. You do not have that option with a soil that is already extremely water-retentive right out of the bag.

I fully understand that many are happy with the results they get when using commercially prepared soils, and I'm not trying to get anyone to change anything. My intent is to make sure that those who are having trouble with issues related to soil, understand why the issues occur, that there are options, and what they are.

We have seen that adding a coarse drainage layer at the container bottom does not improve drainage. It does though, reduce the volume of soil required to fill a container, making the container lighter. When we employ a drainage layer in an attempt to improve drainage, what we are actually doing is moving the level of the PWT higher in the pot. This simply reduces the volume of soil available for roots to colonize. Containers with uniform soil particle size from top of container to bottom will yield better and more uniform drainage and have a lower PWT than containers using the same soil with added drainage layers.

The coarser the drainage layer, the more detrimental to drainage it is because water is more (for lack of a better scientific word) reluctant to make the downward transition because the capillary pull of the soil above the drainage layer is stronger than the GFP. The reason for this is there is far more surface area on soil particles for water to be attracted to in the soil above the drainage layer than there is in the drainage layer, so the water perches. I know this goes against what most have thought to be true, but the principle is scientifically sound, and experiments have shown it as so. Many nurserymen employ the pot-in-pot or the pot-in-trench method of growing to capitalize on the science.

If you discover you need to increase drainage, you can simply insert an absorbent wick into a drainage hole & allow it to extend from the saturated soil in the container to a few inches below the bottom of the pot, or allow it to contact soil below the container where the earth acts as a giant wick and will absorb all or most of the perched water in the container, in most cases. Eliminating the PWT has much the same effect as providing your plants much more soil to grow in, as well as allowing more, much needed air in the root zone.

In simple terms: Plants that expire because of drainage problems either die of thirst because the roots have rotted and can no longer take up water, or they suffer/die because there is insufficient air at the root zone to insure normal root function, so water/nutrient uptake and root metabolism become seriously impaired.

To confirm the existence of the PWT and how effective a wick is at removing it, try this experiment: Fill a soft drink cup nearly full of garden soil. Add enough water to fill to the top, being sure all soil is saturated. Punch a drain hole in the bottom of the cup and allow the water to drain. When drainage has stopped, insert a wick into the drain hole . Take note of how much additional water drains. Even touching the soil with a toothpick through the drain hole will cause substantial additional water to drain. The water that drains is water that occupied the PWT. A greatly simplified explanation of what occurs is: The wick or toothpick "fools" the water into thinking the pot is deeper than it is, so water begins to move downward seeking the "new" bottom of the pot, pulling the rest of the water in the PWT along with it. If there is interest, there are other simple and interesting experiments you can perform to confirm the existence of a PWT in container soils. I can expand later in the thread.

I always remain cognizant of these physical principles whenever I build a soil. I have not used a commercially prepared soil in many years, preferring to build a soil or amend one of my 2 basic mixes to suit individual plantings. I keep many ingredients at the ready for building soils, but the basic building process usually starts with conifer bark and perlite. Sphagnum peat plays a secondary role in my container soils because it breaks down too quickly to suit me, and when it does, it impedes drainage and reduces aeration. Size matters. Partially composted conifer bark fines (pine is easiest to find and least expensive) works best in the following recipes, followed by uncomposted bark in the Bark fines of pine, fir or hemlock, are excellent as the primary component of your soils. The lignin contained in bark keeps it rigid and the rigidity provides air-holding pockets in the root zone far longer than peat or compost mixes that too quickly break down to a soup-like consistency. Conifer bark also contains suberin, a lipid sometimes referred to as nature's preservative. Suberin, more scarce as a presence in sapwood products and hardwood bark, dramatically slows the decomposition of conifer bark-based soils. It contains highly varied hydrocarbon chains and the microorganisms that turn peat to soup have great difficulty cleaving these chains - it retains its structure.

Note that there is no sand or compost in the soils I use. Sand, as most of you think of it, can improve drainage in some cases, but it reduces aeration by filling valuable macro-pores in soils. Unless sand particle size is fairly uniform and/or larger than about BB size, I leave it out of soils. Compost is too fine and unstable for me to consider using in soils in any significant volume as well. The small amount of micro-nutrients it supplies can easily be delivered by one or more of a number of chemical or organic sources that do not detract from drainage/aeration.

My Basic Soils ....

5 parts pine bark fines (partially composted fines are best)

1 part sphagnum peat (not reed or sedge peat please)

1-2 parts perlite

garden lime (or gypsum in some cases)

controlled release fertilizer (if preferred)

Big batch:

2-3 cu ft pine bark fines

5 gallons peat

5 gallons perlite

2 cups dolomitic (garden) lime (or gypsum in some cases)

2 cups CRF (if preferred)

Small batch:

3 gallons pine bark

1/2 gallon peat

1/2 gallon perlite

4 tbsp lime (or gypsum in some cases)

1/4 cup CRF (if preferred)

I have seen advice that some highly organic (practically speaking - almost all container soils are highly organic) container soils are productive for up to 5 years or more. I disagree and will explain why if there is interest. Even if you were to substitute fir bark for pine bark in this recipe (and this recipe will long outlast any peat based soil) you should only expect a maximum of two to three years life before a repot is in order. Usually perennials, including trees (they're perennials too) should be repotted more frequently to insure they can grow at as close to their genetic potential within the limits of other cultural factors as possible. If a soil is desired that will retain structure for long periods, we need to look more to inorganic components. Some examples are crushed granite, fine stone, VERY coarse sand (see above - usually no smaller than BB size in containers, please), Haydite, lava rock (pumice), Turface, calcined DE, and others.

For long term (especially woody) plantings and houseplants, I use a superb soil that is extremely durable and structurally sound. The basic mix is equal parts of pine bark, Turface, and crushed granite.

1 part uncomposted screened pine or fir bark (1/8-1/4")

1 part screened Turface

1 part crushed Gran-I-Grit (grower size) or #2 cherrystone

1 Tbsp gypsum per gallon of soil

CRF (if desired)

I use 1/8 -1/4 tsp Epsom salts (MgSO4) per gallon of fertilizer solution when I fertilize if the fertilizer does not contain Mg (check your fertilizer - if it is soluble, it is probable it does not contain Ca or Mg. If I am using my currently favored fertilizer (I use it on everything), Dyna-Gro's Foliage-Pro in the 9-3-6 formulation, and I don't use gypsum or Epsom salts in the fertilizer solution.

If there is interest, you'll find some of the more recent continuations of the thread at the links below:

Post XIII

Post XII

Post XI

Post X

Post IX

PostVIII

Post VII

If you feel you were benefited by having read this offering, you might also find this thread about Fertilizing Containerized Plants helpful, as well.

If you do find yourself using soils you feel are too water-retentive, You'll find some Help Dealing with Water-retentive Soils by following this embedded link.

If you happen to be at all curious about How Plant Gowth is Limited, just click the embedded link.

As always - best luck. Good growing!! Let me know if you think there is anything I might be able to help you with.

Al

Comments (164)

  • fortyonenorth
    10 years ago
    last modified: 7 years ago

    Well said, Al. Thanks for the reply.

  • tinyfrogs
    10 years ago
    last modified: 7 years ago

    I have only just discovered the amazing Al's mixes threads on GW. I was already using something similar to the gritty mix for my small (and until recently, neglected) bonsai collection. In a few weeks, I will also use my mix when I harvest quite a few landscape plants to begin the conversion to bonsai. I plan to completely leave bagged soils and peat behind, even for the herbs we grow every year. As I embark on a lot of planting and replanting, I hope someone can help me fine-tune my approach. So I could use some clarification on the purpose of granite grit and using the mix for annuals (herbs) from seed.

    I have been using Turface-type material and screened pine bark for a while. I found a local source for Turface MVP ($10 per 50#) just recently. In many years of looking, I have never found a reliable commercial source of pine bark fines. I have access to the slash pile of a small clearcut which gives me as much screened pine bark as I am willing to make myself. I screen to 1-4" to 1/8" and soak and rinse to remove sand and critters.

    What is the role of the granite grit in the mix? Is that to create volume with less water retention than the Turface, so the mix dries out more quickly or the PWL is lower? I haven't been using any non-retentive material in my soils.

    Why the gypsum? Is that just to buffer the pH?

    How can gritty mix be used for herbs? Does it require starting from seed in a fine soil (peaty) and then transplanting, or does anyone actually start their seeds in the mix?

    Thanks.

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  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    As a bonsai failure in my first attempt, I started to study, concentrating on soil science and physiology, primarily. Before I knew HOW, I decided the properties a good soil should have, then I worked toward trying to build those properties into the soils. One of the properties I found desirable was adjustability. I discovered that with just Turface & bark, I needed to add more bark than would allow me to guard against soil collapse, so I came up with crushed granite. I actually discovered it placed on top of a piece of cardboard in a miniature conifer assortment from Iseli's. Since it was white, I presumed it was to reflect light onto the lower foliage and help keep the soil cool. I never asked them why they mulched with it, only where they got it. Then, I started searching for a source, and found several.

    As simple as the gritty mix is, there is a LOT of thought that went into it. The bark is kept at a fraction 1/3 or less, and the grit and Turface make up the remainder in a ratio that can be varied to adjust water retention. The soil is designed and screened so almost all the water is held INSIDE of soil particles. This makes the entire soil mass a healthy place for roots, regardless of container depth and when last watered. There is a lot more, but those are some highlights.

    Gypsum is used as a Ca source when you're using a fertilizer that doesn't have Ca. If the fertilizer doesn't have MG, I suggest you also include a small amount of Epsom salts in the fertilizer solution when you fertilize. Many of us have simply started using Foliage-Pro fertilizer, which has both Ca and Mg, as well as all the other nutrients essential to normal growth. This allows you to set aside concern for supplying Ca/Mg through the gypsum & Epsom salts.

    I regularly use the gritty mix to start seeds & cuttings. Usually though, I'll cover seeds with a thin layer of peat or Turface fines.

    Al

  • skycopp
    10 years ago
    last modified: 7 years ago

    I've got to ask a question and I feel stupid for asking it. As I understand, one of the purposes of the 5-1-1 is to lower the perched water table as well as to have a better draining soil. However, I'm coming to the conclusion that you shouldn't use the 5-1-1 in a self watering container because of the perched water table being lower. In other words, does a well draining soil cancel out the benefits of a self-watering container?
    Anyway, if someone can get me straight, I'd appreciate it.

  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    I think the potential for best growth can be had in containers watered regularly from the top, but there is a lot to be said for the convenience of SWCs.

    Physically, a soil has to be very water retentive to wick water high enough to wet the entire soil mass. That is why SWCs so often employ a vapor barrier atop the soil. You can use a coarser soil with the vapor barrier because water vapor condenses on the barrier & drips down to wet the top of the soil. In general, container soils that wick water high enough to wet the entire soil mass are too water-retentive to offer best growth/vitality .... and soluble salt accumulation can also be an issue in any SWC because it's essentially a closed system with no way out for the salts that go in, except into the plant. A high TDS/EC (salt) level becomes more likely as the planting matures

    If you use a variation of the 5:1:1 mix in a SWC, you'll need to increase the peat fraction to something like 5:3:1, but in the end it depends on how fine the bark fraction is.

    Al

  • skycopp
    10 years ago
    last modified: 7 years ago

    Thanks for clarifying that Al. For now I'll stick with watering the regular way and I'll see how it goes this year. Looking forward to trying the 5-1-1 and hopefully a bigger harvest.

  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    We're ALL pulling for you!

    Al

  • ivanaz
    10 years ago
    last modified: 7 years ago

    Regarding Al's mixes: in Europe where I live two types of Sphagnum peat are being sold (usually mixed together) - 'white peat' and 'black peat'. One is harvested from the top layers of peat and is less decomposed (white) and the other is from the deeper layers, more decomposed (" H5 - H7 according to Von Post scale"). I'm confused because black/white peat is not being mentioned at all in the discussions here. Which one should I use for Al's mixes?

    p.s. Thank you Al and the others for your time and patience in helping everyone here :)

  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    What we use would probably be right in that H5-H7 classification. We usually refer to H1 and H2 as sphagnum moss ..... maybe sometimes H3, too. Product mined from the lower strata that we would be using are more degraded and usually referred to as sphagnum peat. We most often use sphagnum moss in air layers, but often as a pick-me-up (tonic) for roots of stressed plants, too.

    So glad to see a European visitor! Welcome! ..... and thank you for the kind words.

    Al

  • Bob1016
    10 years ago
    last modified: 7 years ago

    Al, what would H10 peat be used for, all I know about it is that it is pretty much muck and won't decompose any more. Can you buy it in the US? What are its uses?

  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    ..... don't know. I know the lower grades of peat are high in salts & inappropriate for most Ag applications. It's probably used as fuel (I know some European power plants are (were?) fueled by low grade peat) or treated as a waste product. It might be used for humification of highly leachable soils, but don't rely too much on anything I said - I'm mainly making only partially educated guesses.

    Al

  • Bob1016
    10 years ago
    last modified: 7 years ago

    That would make sense, if they can burn lignite they can burn that stuff. That might be the step below lignite, I didn't even think of that.

  • ivanaz
    10 years ago
    last modified: 7 years ago

    Al, I was very happy to have had the issue resolved with your speedy and to the point answer, but then I stumbled upon your post I linked to below. Now I'm confused again :( " It's light to medium brown in color, is formed primarily from Sphagnum moss, and is the least decomposed of the general categories of peat." - this seems to describe what's called 'white peat' here - less decomposed, light in color, not 'black peat' which is in H5-H7 range. I'm sorry if I'm nitpicking, but I'm new at this and I'm trying to get my facts right. I used to grow a garden with my dad when I was a kid and enjoyed it thoroughly, I finally have a chance to do it again and I really really want it to work :)

    Here is a link that might be useful: Peat vs. Peat moss-is there a difference??

  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    I'm sorry - I think I misread her question.

    Most of our peat is broken down into unrecognizable particles and quite fine - cocoa brown in color when dry.

    Al

  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    Hey guys!color>

    If anyone would like to encourage a newbie over on the houseplants forum who is trying to decide whether to use a well-aerated mix or a bagged soil, or to offer your thoughts, you'll find the thread at the link below.

    Al

    Here is a link that might be useful: Someone needs your advice .....

  • tecnico
    10 years ago
    last modified: 7 years ago

    hello posters : ) its Dr. Tecnico , saying hello to all here, here is a link to a video , that all interested to see what basic compacted soil can look like after sometime even with proper watering , the plant in general can look ok but when you search the roots and the underneath of the soil you can see a diferent world : ( , could have also given the link to my post on this topic , but it disapperared : O , misteriously : O , with no trace : ( , lol , but no problem ; ) , Dr. Tecnico gonna fix that up when the ingredients arrive and show my transformed peace lily : ) in Al's 5-1-1 mix , hope you enyoy the video oh and by the way pay attention to the bugs and insects thriving inside that soil , : O yikesssss lol , happy gardening to all ; )

    Here is a link that might be useful: peace lily in basic soil

  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    Thanks, Conrado. I don't know what you'd been working on when you tried to post your latest thoughts on your thread, but I'm sure it would have been interesting.

    Take good care.

    Al

  • tecnico
    10 years ago
    last modified: 7 years ago

    hello Al, glad to see u , yes was really long post took 2 hours to round up all the facts and points , but well just posted my video so others can see the things that can happen to "basic un ammended soil " when soil is compacted by time and water gets in the base of the roots , by the way , on this "vacation" lol from my early retired post :p , i have taken time to see the forum and see the wow :O all the plants and beauty they can give when really treated well : )
    and giving them "pent house " type soil-medium for them to thrive ; ) , have to state that at first did'nt understand your concept of the aireated mix , but as you kept explaining and i searched the facts and concepts , it was more clear and reasonable : ) , that plants in well drained and well aireated soil-mediums can do there best : ) , thanks for making clear the concept.

    Conrado

  • ssmdgardener
    10 years ago
    last modified: 7 years ago

    Hey tecnico, so good to see you here! :-) And maybe it's a good thing that the other post disappeared...

    I'm glad you found your way to Al's posts! *Learning* about container culture is what finally gave me the confidence to start growing houseplants again. Nothing like a little education!

    In fact, my peace lily has gotten so lush that it's already outgrowing its container. I honestly think the air in my house is cleaner with all the new greenery.

    But I must confess I didn't watch all 15 minutes of that video... ;-)

  • tecnico
    10 years ago
    last modified: 7 years ago

    hello ssmdgardner , thanks for the greeting : ) , yes indeed it sure makes sound this concept just waiting to get on hands with to see it in action FPV : ) , do you have pics of ur peace lily ??? could u post it here , dont if its appropiate : ( , but maybe it could help other posters see how a good root system makes plants flourish : ) , jeje well the video was edited by the way the whole process took around 35 min so imagine : P , next time will use a more danceable music jeje


    Conrado

  • tecnico
    10 years ago
    last modified: 7 years ago

    Al sent u a message to your inbox

  • tecnico
    10 years ago
    last modified: 7 years ago

    a friend of mines bought a sansiveria plant ( aka - snake plant / mother in law tounge ) and was wondering after buying it from the nursery if it could be planted in the 5-1-1 mix or the grity mix and if the soil that the plant comes with should be taken of ( rinsed - washed ) to use it in the mix or can it be left on ? dont know if taking it off would make any harm or stress on the plant or does with either of the mixes could it make a happy medium transition ?

  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    Yes, please bare-root the plant before transitioning it into a dissimilar soil. If you mix soil types, especially if they are radically different, one part of the soil will always be either too wet or too dry. Sans tolerate being bare-rooted very well - just make sure the plant gets no direct sun for at least 2 weeks after the repot.

    Another thing you'll learn, if you stick around, is that our houseplants need regular repotting, which is different than simply potting up into a larger pot. Repotting includes removing the old soil and pruning off many large roots that serve no purpose other than to act as conduits.

    Some people are not motivated to see that their offerings create more light than heat. They will ignore or obfuscate all facts and reason in an attempt to justify their own needs, forgetting about yours entirely in their quest to avenge some wrong they perceive as having been done to them. I'm sorry you got caught in the middle of that.

    Thanks for the kind words, SS - much appreciated!

    Al

  • tecnico
    10 years ago
    last modified: 7 years ago

    thanks Al : )

    SS, do you have pics of your peace lily that you can post ?

  • Loveplants2 8b Virginia Beach, Virginia
    10 years ago
    last modified: 7 years ago

    Hi Tenico,

    Just wanted to say that im glad your posting again!!!

    I did receive your email and ill get back to you about the Plumeria in PR. You had asked about my time in PR. Just a thought brings to mind...Luquillo Beach and El Yunque are some of my favorite places. I was there at the lost falls before they were discovered before the tourist had a trail marked to get there!! Long ago.. LOL!!! : )

    That is where i fell for the "Coqui" frogs...love those little guys!!!

    You live in a beautiful place and im sure all of your plants and trees will flourish with the wonderful mixes that you are exploring...

    I wish you all the best and i will follow up in your request!!!

    So i want to get back on the OP and say that you will have much success with this mix and im excited to hear how your plants will love this concept. Keep up the enthusiam!! Its quite contagious!! : )

    All the best to you!!!

    Laura

  • tecnico
    10 years ago
    last modified: 7 years ago

    thanks laura how good to see u : ) , and yes will be waiting for your mail on the plumeria's : ) , you know what ? : ) i've been reading a lot and have many projects in the ink bottle , this hooby looks promising : ) and yessss it contagious i looked at your plumerias and i want them , looked at marquest rubber tree and i want them , looked at someones citrus trees ( dont remeber who it was ; P ) and also want them inclusiveeee saw some orchird of josh ???? ( a lot of people so dont know it was his : P ) and also want themmmmmm , you guys and gals, are gonna make me invest in manyyy plantssss lol , but thats the point of planting , seeing how to make the best of plants in the best ways , take care laura : )

    Conrado - Dr. Tecnico

  • tecnico
    10 years ago
    last modified: 7 years ago

    found this at autozone -auto parts store ; read somewhere on the forums that "dry floor" could be used in place of perlite or turface , until now perlite is being dificult to find in small bags other than the MG :( , havent searched for turface but will : ) , so took a pic of the ingredient on bag , could this be useful as a replacement for perlite or turface ?

    its a "dry-floor" small rock type absorbent ,sold in a BIG 8 lbs bag for only 2.90 , so what you think about it ? by the way read that SILICA warning : O , is it dangerous to use ????? for or the plants : O ???? if so well then will keep looking for another substitute , thanks : )

    {{gwi:7285}}

  • tapla
    Original Author
    10 years ago
    last modified: 7 years ago

    ..... not dangerous to the plants, but you do want to avoid breathing in the dust, as you would any other dust from dry soil ingredients. Size is important for the gritty mix. Ideally, you would want a product that is stable and in the 2.5 - 5 mm size range.

    Because it is internally porous, it would be a close replacement for Turface, but holds much more water that perlite, which only holds water on its surface.

    Al

  • tecnico
    10 years ago
    last modified: 7 years ago

    hello Al , how ya doing : ) ? so in that case turface or perlite would be the right way to go right ? i still have more places to keep looking either the perlite or the turface , so i should keep on looking right : ) ? and by the way talking about searching should i look for a smaller pot for my yet to be "operated" PL , cause the pot acording to some where i read , should be a 1 or 2 inch bigger than the roots , so upon dividing the PL the roots will be small for that big pot it is in now , by the way what is the correct way to measure the pots , have read about 5 inch - 8 inch , etc etc , is that the height , how do i know which size is my pot ????

  • tecnico
    10 years ago
    last modified: 7 years ago

    by the way Al , i sent you a message about the fertilizers , in your inbox ; )

    Conrado

  • skycopp
    10 years ago
    last modified: 7 years ago

    Well,
    yesterday I attempted to make my first batch of 5-1-1 but I am not sure I did it right. I used these ingredients:
    http://www.lowes.com/pd_92118-66882-92118_0?productId=1112345&Ntt=pine+mulch&pl=1&currentURL=%2Fpl_0_s%3FNtt%3Dpine%2Bmulch&facetInfo=

    http://www.lowes.com/pd_156581-446-74278300_0_?catalogId=10051&productId=1036853&UserSearch=perlite&Ntt=perlite&N=0&langId=-1&storeId=10151&rpp=24

    http://www.lowes.com/pd_328590-10799-1310502_0?productId=3319756&Ntt=peat+moss&pl=1&currentURL=%2Fpl_0_s%3FNtt%3Dpeat%2Bmoss&facetInfo=

    and a some dolomite garden lime for which I cannot find a link for, but it was real powdery.

    My formula was roughly 7 gallons of Pine bark, 1.3 gallons each of perlite and peat moss, and about 9 tablespoons of garden lime.

    I mixed it all up and planted some mustard seeds in it, but I have this feeling that I goobered this up by using pine mulch and not pine fines. Did I use the right stuff?

  • ssmdgardener
    10 years ago
    last modified: 7 years ago

    Skycopp, I'm also in MD. I can help you find all the ingredients. Are you closer to Baltimore or DC?

    I just recently learned (I think yesterday) that there are different grades of perlite. The kind I get is very coarse, but from what I understand, MG perlite tends to be very powdery.

    Your peat moss looks ok, but you might not have needed that lime. See how your peat moss package says it's enhanced? Sometimes they already have the lime included to adjust the ph. Al can probably give you a better answer about the lime.

  • skycopp
    10 years ago
    last modified: 7 years ago

    I'm actually in the Gaithersburg and Rockville area.

    Thanks for your comments, this was a test batch before I really started to get going with my tomatoes and peppers.

  • ssmdgardener
    10 years ago
    last modified: 7 years ago

    The best bark fines I've found are at Behnke's Nursery. They have a huge garden center in Beltsville and a smaller one near you in Potomac.

    Just ask for "pine bark fines." You'll notice immediately that the texture is totally different from "pine mulch."

    They also carry Espoma perlite, which has a nice coarse texture

    I actually get my peat moss in huge bags at HD or Lowes.

    Al recommends that you screen the ingredients. I've never planted seeds in the 5:1:1 mix, but I imagine this screening process is particularly important for seeds, as you don't want them to fall through coarse pieces of bark and fall to the bottom. (I'm hoping someone with more experience will chime in here.)

  • skycopp
    10 years ago
    last modified: 7 years ago

    Thank you for the tips!!
    I didn't even know about Behnke's. I have a Meadows Farms Nursery (http://meadowsfarms.com/Home.aspx) just down the road, but they are closed until March. If Behnkes is open, I will have to stop in and get those items you mentioned. Hopefully the prices are not too high as compared to Lowes, because I'm really needing enough to fill ~50 containers.

  • ssmdgardener
    10 years ago
    last modified: 7 years ago

    Glad to help! Behnkes is most definitely open.

    I've been to both nurseries, and IMHO, there is no comparison :-)

    Pine bark fines are definitely more expensive than regular pine mulch. I'd say probably twice as expensive, but well worth it.

    I'm still hoping someone else chimes in with specific advice about starting seeds in the 5:1:1 mix.

  • Linda
    6 years ago
    last modified: 6 years ago

    Hi Al,

    What do you recommend specifically for Japanese Maples in the Gritty Mix, including gypsum, Dyna-Gro's Foliage-Pro in the 9-3-6 formulation, source of micronutrients, weak continuous fertilizing, watering schedule, and whatever else comes to mind regarding JMs in containers.... I am in the Seattle area, in need of recommendations for suitable bark, grit and Turface sourcing. Thank you for all your work and kind words.


  • tapla
    Original Author
    6 years ago

    Hi, Linda. I've been furiously repotting this last week and am finally at a pause point, albeit a a brief one.


    Sometimes I'll put BIG trees (3-4" diameter trunks) recently dug as future bonsai candidates in the 5:1:1 mix to test the theory that JMs like a large organic fraction in their soils, but so far, reality hasn't sided with that notion. I use the gritty mix, FP 9-3-6 withheld until the spring flush of growth has matured, and judicious pruning/ disbudding to keep maples neat. It's important to pinch the center growth from all but the weakest branches as leaves are emerging in the spring. This will help eliminate those 6" long internodes you see on some trees whose appearance has been destroyed by same. As soon as the first pair of leaves opens from a bud, be looking for the center to pinch out. I often have to separate the first pair of leaves to get at the center branch. Let me know if you need a picture to help clarify.

    With the FP, you won't need micronutrients, but you can add Micromax to the soil when you make it if you like, or use water soluble STEM very sparingly. I used to use both before I started using FP 9-3-6, but now rarely use anything additional, other than ProTeKt 0-0-3.

    I'm thinking you should be able to find fir bark in abundance there, so call around - look for bonsai clubs and ask tyo talk to their soil guy or whomever else might be able to source it for you. Given your proximity to the source of shellfish, I'm guessing you'll probably need to use Manna-Pro Poultry Grit for the grit part, but don't overlook lava if it's around the 1/8" size. Sources for Turface MVP near Seattle:

    When I did a search For John Deere Landscapes (a reliable supplier of Turface Allsport, which is the same as Turface MVP) I kept coming up with "Home -SiteOne". Anyone know anything about JDL being acquired? If you don't find what you need above, try asking the JDL or SiteOne dealers for Turface MVP or Allsport.

    I hope that helps.

    Al

  • Linda
    6 years ago

    Yes, that helps! How and when do I apply the "Dyna-Gro ProTeKt 0-0-3" to the Japanese Maples? Thank you Al.

  • ethanqsimmons
    6 years ago

    Is hydrated silica an acceptable substitute for Turface? Specifically, I'm looking at this Oil-Dri product: http://www.walmart.com/ip/OIL-DRI-I05090-G40-Granular-Clay-Absorbent-50-lb.-Bag-G6125664/41023709

  • tapla
    Original Author
    6 years ago

    L - the best way to apply it is to fertigate with the 9-3-6 solution, followed by the 0-0-3 ProTeKt applied the next time the plant needs water. The 2 products don't mix well in the same container/solution - and you should always avoid mixing them together in their concentrated form - no danger - just that some of the nutrients precipitate.

    Ethan - If the particle size is appropriate and you're left with enough product after screening to make it a financially sound investment (from your perspective), and the product is fired at temps high enough to make it stable - it should work fine as a Turface sub. To test stability - freeze overnight in a plastic cup with water. If it's stable when it unthaws, instead of mud, it should work well.


    Al

  • mblan13
    6 years ago

    Al, Id like to see that pic of the JM pinching. How late is too late to pinch? My JMs leafed out late March.

  • tapla
    Original Author
    6 years ago

    I think pinching J maples is a little off topic for this forum, so I started another post. You can get to it by following this embedded link.


    Al

  • jer348
    6 years ago
    last modified: 6 years ago

    Maybe try this one http://www.amazon.com/

  • tapla
    Original Author
    4 years ago
    last modified: 4 years ago

    Thanks for the kind words, B&C.

    In Mississippi, Memorial day would be a good target date for repotting the fig.

    Hibiscus need an annual repot. Do that toward the end of March, before it starts growing in earnest.

    Apple and most deciduous trees should be repotted just before or at the onset of spring budswell.

    Cactus - ask the cactus experts at the cacti/succulents forum.

    Desert rose - in Mississippi - June

    Umbrella plant - June

    There are ways to mechanically limit the amount of perched water a planting will hold, even if you're using a very water-retentive medium. Eliminating all or most of the perched water allows the grower to use media that would otherwise be or border on the edge of unusable. This outlines ways to cope with heavy (water-retentive) media

    Another effective way of dealing with media that hold too much water is through the use of ballast. You can read more about that technique here: Ballast .....

    For now, checking your planting's moisture level regularly with a 'tell' will make a difference in your plant's appearance and level of vitality. Here's something I wrote about that:


    Over-watering saps vitality and is one of the most common plant assassins, so
    learning to avoid it is worth the small effort. Plants make and store
    their own energy source – photosynthate - (sugar/glucose).
    Functioning roots need energy to drive their metabolic processes, and
    in order to get it, they use oxygen to burn (oxidize) their food.
    From this, we can see that terrestrial plants need air (oxygen) in
    the soil to drive root function. Many off-the-shelf soils hold too
    much water and not enough air to support good root health, which is a
    prerequisite to a healthy plant. Watering in small sips leads to a
    build-up of dissolved solids (salts) in the soil, which limits a
    plant's ability to absorb water – so watering in sips simply moves
    us to the other horn of a dilemma. It creates another problem that
    requires resolution. Better, would be to simply adopt a soil that
    drains well enough to allow watering to beyond the saturation point,
    so we're flushing the soil of accumulating dissolved solids whenever
    we water; this, w/o the plant being forced to pay a tax in the form
    of reduced vitality, due to prolong periods of soil saturation.
    Sometimes, though, that's not a course we can immediately steer,
    which makes controlling how often we water a very important factor.


    In many cases, we can judge whether or not a planting needs watering by
    hefting the pot. This is especially true if the pot is made from
    light material, like plastic, but doesn't work (as) well when the pot
    is made from heavier material, like clay, or when the size/weight of
    the pot precludes grabbing it with one hand to judge its weight and
    gauge the need for water.


    Fingers stuck an inch or two into the soil work ok for shallow pots, but not
    for deep pots. Deep pots might have 3 or more inches of soil that
    feels totally dry, while the lower several inches of the soil is 100%
    saturated. Obviously, the lack of oxygen in the root zone situation
    can wreak havoc with root health and cause the loss of a very
    notable measure of your plant's potential. Inexpensive watering
    meters don't even measure moisture levels, they measure electrical
    conductivity. Clean the tip and insert it into a cup of distilled
    water and witness the fact it reads 'DRY'.


    One of the most reliable methods of checking a planting's need for water
    is using a 'tell'. You can use a bamboo skewer in a pinch, but a
    wooden dowel rod of about 5/16” (75-85mm) would work better. They
    usually come 48” (120cm) long and can usually be cut in half and
    serve as a pair. Sharpen all 4 ends in a pencil sharpener and
    slightly blunt the tip so it's about the diameter of the head on a
    straight pin. Push the wooden tell deep into the soil. Don't worry,
    it won't harm the root system. If the plant is quite root-bound, you
    might need to try several places until you find one where you can
    push it all the way to the pot's bottom. Leave it a few seconds, then
    withdraw it and inspect the tip for moisture. For most plantings,
    withhold water until the tell comes out dry or nearly so. If you see
    signs of wilting, adjust the interval between waterings so drought
    stress isn't a recurring issue.

    Al

  • PRO
    Byrd and Cook
    4 years ago

    I also have a majesty palm I got on markdown that looked OK but needed some love that I’ll probably need to repot. Best time for those and gritty mix for it?

    tapla thanked Byrd and Cook
  • tapla
    Original Author
    4 years ago

    June


    Al

  • michael_europe_zone8b
    3 years ago

    Hello Al, from (for now) sunny & warm Belgium!

    For more than two years I learned a lot almost every day, reading and digesting this high quality information that you and a few others so kindly and generously share with all of us here. For this I need to say a big Thank You!

    People visiting my place admire the beautiful plants and think I'm good at it, thanks to you and the knowledge shared here on GW. I just say "I have good teachers":)

    It has made an enourmous difference in my approach to caring for my house plants (a few citrus, plumerias, jades, mexican fan palm).

    My first mix (for the plumerias & jade) was with 4 Pumice + 3 Reptibark + 2 coarse Perlite and so far was 100% reliable.

    Turface and crushed granite are absent in Europe and following your kind advice, I used Pumice.

    I intend to make a new batch of gritty mix: 4 Seramis clay granules + 3 Reptibark + 2 coarse Perlite. I will screen all ingredients.

    I went for Seramis (which is, btw, of great quality in terms of size and absence of residuals) since I cannot get pumice anymore.

    Do you recomend using the Seramis by the same proportion I used Pumice in my first batch? (Assuming that Seramis has similar properties like Pumice)

    Thank you again for all the wonderful advice you offer.

    Michael (Belgium/Brussels zone 8b)


  • Tanner B. Hess Webber
    last year

    I just started using the gritty mix and it seems to be doing well, but it kind of feels a bit "magical"... I haven't had an opportunity to run any tests, but if I pour a cup of water into a two gallon pot, it seems that 3/4 of a cup or more comes out. Is there a better way of watering?


    For my larger container plants, I've actually switched to spraying the water onto the medium so that gravity and capillary action aren't as big of a factor. The problem that I run into is that I can't spray on my fish emulsion. Is that even the right fertilizer to be using in this kind of medium?


    I have five plants in the medium at the moment, and they are all happy aside from two aloes. Is there something that I'm missing about aloe in this type of medium?


    Thanks in advance and I apologize if these have been answered before... There are just too many comments to read through!