FIND PROFESSIONALS
SHOP BY DEPARTMENT
Houzz Logo Print
webuser_355114

Container Soils - Water Movement & Retention VIII

tapla
13 years ago

I first posted this thread back in March of 05. Seven times, it has reached the maximum number of posts to a single thread (150), which is much more attention than I ever imagined it would garner. I have reposted it, in no small part, because it has been 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 hopefully, the exchanges provide helpful information. Most of the motivation for posting this thread again comes from the participants reinforcement of the idea that some of the information provided in good-spirited collective exchange will make some degree of difference in the level of satisfaction of many readers growing experience.

I'll provide links to the previous seven threads at the end of what I have written - in case you have interest in reviewing them. Thank you for taking the time to look into this subject - I hope that any/all who read it take at least something interesting and helpful from it. I know it's long, but I hope you find it worth the read.

Container Soils - Water Movement and Retention - A Discussion About Soilssize>color>

As container gardeners, our first priority should be to insure 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. 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 IÂll 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 as an 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:

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 enough nutrients in available form to sustain plant systems. Gas Exchange - It must be sufficiently porous to allow air to move through the root system and by-product gasses to escape. Water - It must retain water enough in liquid and/or vapor form to sustain plants between waterings. 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 of water in 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, waterÂs bond to itself can be stronger than the bond to the object it might be in contact with; in this condition it forms a drop. 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 .125 (1/8) inch.. This is water that occupies a layer of soil that is always 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 perched. The smaller the size of the particles in a soil, the greater the height of the PWT. This water can be tightly held in heavy (comprised of small particles) soils and Âperch (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, and 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. 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: 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 drain better. 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?

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 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 starve/"suffocate" because there is insufficient air at the root zone to insure normal water/nutrient uptake and root function.

Bark fines of fir, hemlock or pine, 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 natureÂs 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.

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 havenÂt 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 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 ½ BB size I leave it out of soils. Compost is too unstable for me to consider using in soils. The small amount of micro-nutrients it supplies can easily be delivered by one or more of a number of chemical or organic sources.

My Basic Soils

5 parts pine bark fines

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)

micro-nutrient powder, other continued source of micro-nutrients, or fertilizer with all nutrients - including minors

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)

1/2 cup micro-nutrient powder (or other source of the minors)

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)

micro-nutrient powder (or other source of the minors)

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 vigor closer to their genetic potential. 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, pea stone, coarse sand (see above - usually no smaller than ½ BB size in containers, please), Haydite, lava rock (pumice), Turface or Schultz soil conditioner, and others.

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

1 part uncomposted pine or fir bark

1 part Turface

1 part crushed granite

1 Tbsp gypsum per gallon of soil

CRF (if desired)

Source of micro-nutrients or use a fertilizer that contains all essentials

I use 1/8 -1/4 tsp Epsom salts per gallon of fertilizer solution when I fertilize (check your fertilizer - if it is soluble, it is probable it does not contain Ca or Mg.

Thank you for your interest.

Al

If there is additional interest, please review previous contributions to this thread here:

Post VII

Post VI

Post V

Post IV

Post III

Post II

Post I

Some readers might also be interested in a discussion about fertilizer strategies for containerized plants at the link below.

Comments (150)

  • yellowthumb
    13 years ago
    last modified: 7 years ago

    Thanks Al, I appreciate it.

    My pine bark is too big, actually twice as big as yours. What would be the problems for the barks being too big, I guess the mix would be less water retentive. Right? I am going to take a picture of mine mix tomorrow.
    What kind of tools I could use to chop it smaller, I remember you mentioned chipper. Could you recommend a model? I have the pine bark mini nuggets, but it's still too big and the quality varies so much for different bags.
    YT

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

    If the other 2 ingredients are the right size, the bark being too large isn't that large a problem. It DOES reduce the room for the roots, but it really won't much alter the drainage or aeration characteristics of the soil (again, if the other 2 ingredients are the right size).

    I have no idea what model chipper would be suitable - sorry. I've never used one, and I have no difficulty locating suitable bark.

    Good luck. ;o)

    Al

  • Related Discussions

    Water feature

    Q

    Comments (46)
    Ann - I love your brick and yard match as well! I can't wait to see it in a few years when the plants fill in. We did get some kind of blue grass ( I can't remember the name off hand) to fill in behind and some ground cover to finish off the area. I am happy with it ... now on to the next project! Thank you all for your input!
    ...See More

    Soil Smack Down: Peat Moss vs. Coconut Coir: Compost Wins!

    Q

    Comments (10)
    The idea that agricultural use of peat contributes to an unsustainable harvest rate is far from the truth. I would concede the point if everyone in Canada and the northern tier of states was burning it as fuel, but consider: In Canada alone, there are more than 270 million acres of harvestable peat bogs - that's harvestable. Not taken into account are the millions of additional acres of bog that are not deemed harvestable because of their size or location. If we make the conservative guess that the harvestable portions of these bogs are 10 feet deep, that means there are probably more than 900 billion cu. ft. available for harvest, just in Canada! That doesn't even take into consideration what's available in Europe, Asia, or places like New Zealand where they also mine peat. Canada currently has mining/harvesting operations underway on approximately 40 thousand acres or about .014% (that reads 14 one thousandths of 1 percent) of their harvestable peat. You'll find the math accurate and conservative. It's more likely that the next Laurentide Ice Sheet will be upon us and glaciers will have covered what's available before we even use a notable fraction of one percent. As peat bogs grow, their depth is increased by a paltry 1mm per year, approximately. Based on current harvest rates in North America, peat is accumulating at a rate approximately 70x greater than what is being lost to harvest. You can probably tell I don't feel guilty about using peat. I agree that both peat and coir can be left out of the lawn/garden equation altogether, and compost would also be my first choice as a top dressing or soil amendment, but we part ways again when we turn to use of peat vs coir or compost in container media. Peat and coir have moisture retention curves that are close enough you would be hard pressed to say one has much advantage over the other. Coir does have less loft (so less aeration) and tends to compact severely if watered from the top or used as a large fraction of a medium - more than 25%. For this reason, most greenhouse ops that use significant amounts of coir in their media sub-irrigate. Too, one should not think all that needs to be done is substitute coir for peat in container media and all will be well. Coir is chemically different than peat and requires work-arounds if we are to avoid unnecessary limitations of plant potential. For example, coir is often high in salinity and can contain toxic levels of Na. It has an extremely high K content, and it's notably higher pH (than peat) means dolomite is not suitable as a liming agent/source of Ca/Mg. Gypsum should be used as a Ca source, which acts remedially to fix coir's low S content as well. My go to medium for garden display containers/veggies is (by volume): 5 parts pine bark (dust to 3/8) 1 part perlite (medium - soil mix grade) 1 part peat (more or less - depending on the particle distribution of the bark) Dolomite Micromax I've done a number of comparisons between plants grown in the medium above, contrasted with media in which I substituted coir for peat or CHCs for the pine bark, and the results were extremely telling ..... which is what started my investigation into coir and why it might be performing so poorly. What I use for short term container plantings - no more than 2 years: What I use for long term plantings - woody material growing on as potential bonsai, and refined bonsai; succulents; cacti; anything that might be in the same medium for more than 2 years: It's equal parts by volume of screened pine or fir bark, screened Turface MVP, and screened granite in grower size or screened quartzite in size 2. There are no fine particles in this mix. Some mixed plantings: Al
    ...See More

    red cedar in contaner soils?

    Q

    Comments (1)
    Also are there negative effects of using the red cedar for mulch around citrus trees, flower beds, or pine trees? If there are, are there specific plants or plant groups that cedar should not be used as a mulch around?
    ...See More

    Switching Monstera to 5-1-1 mix

    Q

    Comments (4)
    Mine seems like the toughest plant. I have had mine maybe 20 years, it's quite large, and I don't even know if there's much soil left in the pot. It goes outside in filtered light when it warms up, gets watered sometimes, and then I bring it in in the winter. It usually dries out in the winter and the leaves might turn yellow and die. This winter it must be getting enough light and water from my cat's partly empty bowls that I toss on the plant. It is still green in a dim bathroom. My point is, once your plant gets established you might not have to fuss over it. I'm not sure how to advise you to get it to survive at this stage. It does look like kind of a fine, dark soil. I do not know what the 5 1 1 soil is but assume it drains better. I voted to pot up in your new soil mix now but have no idea how fast it'll dry out and that's a concern since you're going on a trip. I think the original potting soil I used was MIracle Grow.
    ...See More
  • yellowthumb
    13 years ago
    last modified: 7 years ago

    Thanks Al for your fast response.

    The other two seems alright. I have a plant and feed company locally, they have the Turface MVP and the chicken grower girt, the owner is actually knowledgeable with container garden too. He knows many bonsai grower here. When I was talking about the girt and the moment he knew that I was doing container gardening, he told me the grower size and strongly recommended the turface MVP too.

    In your second picture, is that a quarter?

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

    Yes - those bonsai guys usually know where to find soil ingredients or how to twist someone's arm to get them to stock them. ;o)

    The second is a pic of the same soil as the third, just a close-up. All three coins are dimes.

    Al

  • llatchford
    13 years ago
    last modified: 7 years ago

    I have planted a 1 year Tango mandarin citrus in a 8"x 8" wire (hanging type) basket with a coir liner. This for me is an experiment, as I am trying to maximize growing conditions for citrus (opposed to plastic pots). To offset the quicker loss of water, I have included a bit more peat to the mix to retain some moisture (instead of 1 part, closer to 2 in a 5-1-1 mix).

    Incidentally, I bought a large amount of what the bag said was spagnum peat earlier this summer, but now looks to be the smaller, denser type when compared to your picture of the spagnum you posted.

    Do you see any inherent error in attempting this? Thanks for your help. Laura

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

    No errors, but I think you'll need to be ever at the ready with the watering can. ;o)

    Al

  • lesmatzek209
    13 years ago
    last modified: 7 years ago

    good morning al,

    i am building 26 inch wide by 16 foot long by 26 inche,s deep raised bed,s in my greenhouse, how can i make a good
    true soil (not potting soil) to fill them with ? thank,s.
    ps they are on concrete floor,s.
    les matzek

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

    There are recipes that give very good starting points in the very first post at the top of this thread. If you have specific questions about how to alter them to achieve a specific soil trait, then be sure to ask.

    Al

  • filix
    13 years ago
    last modified: 7 years ago

    Hello Al. Hope you don't mind me asking something I should know by now. Is the reason why you like composted pine bark in the 5.1.1 Because you might get nitrogen problems with uncomposted. Or because composted is easier to get better size? The reason I ask is because I can get uncomposted for such a good price. And i don't want to go through the problem of having to try to compost it , if i don't really need to. Thankyou. filix.

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

    You can use uncomposted PBFs if you have them, with no problems. You're right though, there is a tendency toward reduced N immobilization in the partially composted product. Remember too - particle size is the key consideration. I'm using Fafard's Aged Pine Bark this year & am finding it too fine to suit my style of growing (which means I should probably have added at least another part of perlite in this year's soils). I'm hoping things straighten out soon as the plantings get fully mature, and I see evidence that it is. I'll be returning to my regular source of bark for next year's soils.

    Al

  • filix
    13 years ago
    last modified: 7 years ago

    Thankyou Al. I also figure when I buy fresh bark, I know whats in there. This year i tried some very old bark "30 year or more" That was ground up recently and some fresh fines mixed in. Who knows what was in there. I have a couple of containers with morning glorys that are just sitting there. Hardly growing at all. Hope i wasn't to heavy handed with the lime. I never measure that stuff.

    On another note.Remember My friend with the window boxes? I thought he was going to bring that faster mix by fafards. Well he showed up with the same peat based junk. I think the guy at the greenhouse talked him out of it.I could have cried. Then I tried to talk him into at least putting a wick in the bottom of his 30 gallon cement containers. He looked at me like I had two heads. He was sure the rope would block up the holes. So thats four tree form six foot gardenias in almost mud. He asked me if I wanted them at the end of the summer. I cant Imagine trying to over winter those in that soil. filix.

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

    Different strokes ..... :o)

    Al

  • lathyrus_odoratus
    13 years ago
    last modified: 7 years ago

    I've decided to get some African violet leaves and start plants. Since this is a plant that definitely hates wet feet, but needs regular water, a container environment is basically what is used. Some people wick their containers and others use capillary matting. Yet others place one container inside a second container - such as an unglazed pot inside a plastic pot, allowing the water to move through the unglazed pot. And, yet another group puts water in an outer pan for an hour, letting the plant take in the water it needs, then dumps the unused water.

    I have purchased two containers - one style that wicks, and one with capillary matting. I figured I'd try that style first.

    Now I just have to decide what mix to use. Many people use a 1:1:1 of peat, vermiculite and perlite. Some throw in 2 parts of perlite.

    Anyone here have any experience with these plants grown in a container environment?

    I'm also posting in the AV forum; most people there stick with the 1:1:1 or 1:1:2. I figure I'll follow their lead on the starting of the leaves, but just wondering if there might be an alternative for the mix for the plants.

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

    I've had very good luck using the gritty mix for AVs.

    Al

  • lathyrus_odoratus
    13 years ago
    last modified: 7 years ago

    Glad to hear you've used it for them. I thought the gritty mix would work in terms of drainage and not staying too wet and even potential pH. Not sure why I thought it might not be "delicate" enough - thought maybe the roots would have a harder time with it.

    May I ask how you were watering? I'd be using a wick, most likely.

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

    I watered from the top, being as careful as I could not to soak the crown - easy to do with such a fast soil.

    Al

  • katskan41
    13 years ago
    last modified: 7 years ago

    Yesterday, when watering my conifers growing in the gritty mix, I noticed several of the trees had roots growing out of the drainage holes at the bottom of the 1 gallon containers. They are sticking out about 1 or 2 inches. That's really amazing since I heavily root pruned these trees in March and April when they were potted up and the roots were nowhere near that size.

    I removed about 1/4 to 1/3 of the roots at that time and already they've recovered enough to stick out of the container. Must be a very healthy root system being built in those containers.

    Anyway, should I cut off the roots sticking out of the containers? The containers sit directly on top of the soil and might actually begin growing into the soil if they are not pruned.

    Thoughts or suggestions?

    Thanks

    Dave

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

    I would allow them to grow into the soil, which will speed their development, but not so long it becomes a problem to lift them. The drawback is that the plant will develop it's feeder roots on the roots extending aggressively and build its canopy based on water/nutrients those roots are capable of supplying , so when you lift them you need to be conscious of other cultural conditions (temp, wind, sun exposure) so you don't jeopardize adequate water/nutrient uptake when you lift them (usually not much of an issue with pines, but can be problematic with spruce/fir).

    Al

  • citygirlgardener
    13 years ago
    last modified: 7 years ago

    Al:

    WOW. Learned through another posting that there was a couple of soil gurus in the container gardening section and I guess they were right. It is to late in the season for me to try your soil mixture and I didnt even lighten my soil mix in my cucumbers or melons at all, did in my tomatoes. I want to try the wick in the melons and cucumbers, to try and rid the containers of some of the water. Should I just use a untreated piece of cloth rope and push it into the soil, how far out the top do I leave the wick (hanging over the side)?

    These are my cucumbers and melons, relatively:
    {{gwi:32595}}
    {{gwi:32596}}

    Below are some of my tomatoes:
    {{gwi:32599}}

    My potatoes:
    {{gwi:32601}}

    Any help you can provide would be helpful, thank you and Happy Gardening!

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

    Hi, CGG. Welcome! ;o)

    {{gwi:3289}}

    Your plants look like you're doing just fine & don't need a whole lot of help. Good job!

    I use strands from rayon mop heads. I JUST got this in my email yesterday from a friend in CA. She sent it to me because she knew I'd prolly want to share the info with others. It seems that you can buy the mop heads at Ace hardwares, but not ALL of them, but this one is sold @ Wally World. Here's what she says: "Here's the info on the rayon mop head. Brand is Mainstays Home (Walmart's house brand), clear bag with a wide taupe and sage green band across the front, product called 'Cushion Head Jumbo Rayon Mope Refill', SKU 4683100014. Actual manufacturer J.W. Manufacturing Co, Mineral Springs, AR 71851. ( made in the USA ;-) ) There is a cotton version in similar packaging so advise your friends to check label carefully."

    You only need to push the wick far enough into the drain hole so it stays put. You should allow it to dangle at least 2-3" below the container, or allow it to be in contact with soil below the container. Alternately, burying your container a few inches deep so the drain holes are in the soil will accomplish the same thing.

    Take care.

    Al

  • citygirlgardener
    13 years ago
    last modified: 7 years ago

    Thank you so much. I would have bought cotton, not rayon. Again, great post, keep up all the helpful info. Happy Gardening!

  • lathyrus_odoratus
    13 years ago
    last modified: 7 years ago

    Fascinating....I went to a couple of big box stores yesterday to see if I could find ANY of the things in the gritty mix. Only one was available - pine park mulch, but it looked a bit small for the gritty mix. I literally wrote down every potential alternative and none were to be had.

    It's actually worse being in a large city than in the suburbs or country. No one assumes that city people want to garden! In the houseplant section, I couldn't fine ONE pre-made mix that didn't have fertilizer added. Since my bike in my primary mode of transport, this makes it a bit difficult to do some of this stuff.

    Fortunately I can rent a car through the car sharing program I belong to. It just seems so odd to me that I'd have to do that.

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

    If you read carefully, you'll find lots of useful tips (upthread) on where to find the ingredients. The only thing you MIGHT find at a big box store is the bark. The other ingredients will take some scouting. There is a Turface (MVP) locater here (cut paste to your browser):
    http://www.profileproducts.com/en/sports_fields/wheretobuy.htm

    The granite can be had at rural feed stores/grain elevators. You want Gran-I-Grit 'grower' size or #2 cherrystone. An alternative to Turface is NAPA floor-dry - available at NAPA Auto Parts stores.

    Al

  • xxx1angel3xxx
    13 years ago
    last modified: 7 years ago

    al I am wanting to overwinter some hot peppers this year
    they will be in 1 and half gallon pots with water pans underneath will this be enough
    I am also planing to use the gritty mix with CRFs in it
    but my goal is to not have to re pot them untill next spring is this even remotely realistic with a plant that grows as fast as most peppers do I'm thinking it will take them longer to fill the pot with the gritty mix but maybe I'm wrong from what I've read thats what most would use for perennial bushes and from what I've read that what peppers are so is this a good idea
    would you modify anything mix wise to do this
    thanks al
    btw I have many happy veggies because of what I've learned from your posts so thank you

  • justaguy2
    13 years ago
    last modified: 7 years ago

    Angel,

    The gritty mix will be fine for overwintering your peppers.

    What is the purpose of the water pan under the pot?

    Unless you keep your peppers under HID lighting indoors I wouldn't worry about them growing too fast. In most cases overwintered peppers don't grow much until days have lengthened considerably. Until then they tend to start looking like crud and some varieties will simply die. It's just the way it goes.

    I would recommend a root pruning and a top pruning before potting for overwintering. I would recommend the pruning of the roots and top growth be drastic. Both should just be remnants of their former self. Less stuff for bugs to attack, less leaf mass to transpire water in typically dry winter homes etc. You don't even need to leave any leaves on the plant, the drastic pruning will result in it pushing out new growth instead of having to deal with the old growth that isn't well adapted to the indoor conditions.

    If you don't prune this way and instead bring the entire plant inside you will most likely just watch as it drops leaf after leaf over the winter anyway ;)

    Anyway, the gritty mix is a good choice for overwintering this plant. It's not a bad choice for growing it outside either.

    You might wish to head to the hot pepper forum on GW and do a search on overwintering for some experiences others have reported and the techniques they use.

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

    Where will you be over-wintering (light/temps)?

    Al

  • justaguy2
    13 years ago
    last modified: 7 years ago

    the pan under the pot will be to catch any water that comes out of the holes when watering then dumped as I understand the peppers don't like to set in standing water

    Very few plants do. Thanks for that explanation. they are only seedlings right now so do I still need to do the pruning

    No. the pruning is for large, well established outside plants coming in for the winter and having to adjust to much lower light/humidity/temperature levels for the duration. I was sorta hoping to still get a few peppers

    Not likely when overwintering without strong supplemental lighting. Even if it does occur I wouldn't allow it as it will just sap energy from the plant for something that won't develop properly. What you are hoping for with overwintering is survival, not thrival, unless lighting, temp and humidity issues are addressed. Otherwise think low stress for the plant, not high.

    Anyway, I would be happy to discuss this with you further, but if you would like to do so I recommend it be taken to a separate thread in this forum or a thread in the pepper forum. It is a bit off topic for this thread.

    Please don't take that as criticism as it's not at all meant to be, just saying that to go multiple iterations on this thread on the topic of overwintering peppers seems out of scope to me for this thread.

  • xxx1angel3xxx
    13 years ago
    last modified: 7 years ago

    ok I meant no disrespect I just had a lot of questions about things I had not thought about I will use the gritty mix for my soil medium which was my real question for this thread anyway I'm sorry bye.

  • msaunt
    13 years ago
    last modified: 7 years ago

    Just an update, and thanks again everyone for all your advice. The repotted plants are doing very well in the MG. Now, we've just had about 5 days of rain, so even the tops of these have some algae if they were under row cover. ugh. I'm letting everything 'dry up' for a couple days. I had a couple of pots left with the old soggy mix at my mother's house. I had to repot one of her tomatoes yesterday as the root ball was dying, that thing was totally waterlogged after all this rain. On the plus side, anywhere I dumped the old mix, plants are thriving. There are two more pots at Mom's with the old mix, and then it's all gone. I bought another 2.5CF of MG yesterday, so it's at the ready if those get too wet. I think those pots have better drainage holes so maybe that's saving them.

    Thanks again everyone, I learn tons on this site!

  • rj_hythloday
    13 years ago
    last modified: 7 years ago

    I finally got around to screening my pine bark and got some napa floor dry and screened that w/ window screen. Repotted a couple house plants and pulled some lettuce out of the garden that I want to keep from bolting and grow under lights indoors. I'm going to start some more lettuces for indoor growing also.

  • pardak
    13 years ago
    last modified: 7 years ago

    I've just mixed up some 5-1-1 and it looks great for growing all kind of flowering plants and veggies. It's probably too late in the season now to plant in it but next year I'll try this for most of my tomato plants.

    For the grit mix, can I substitute pea gravel for the granite? I see end of season sales on gardening supplies like pine bark and pea gravel and wonder if I could use a 1-1-1 mix of pine bark, turface and pea gravel in containers for woody plants? A 50# bag of pea gravel is about $2.00 on sale, which is close to what I pay for a 5# bag of granite. Would pea gravel make the soil drain too fast? the gravel looks to be between 1/4" and 1/2" in size but the edges are rounded instead of sharp like granite.

    thank you.

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

    To get the most benefit from the soil, you need to have the ingredients reasonably uniform, equal in size, and around 1/8". You could probably get the soil you suggest to work, but it won't be as plant friendly as if you used granite instead of peastone. It would be better if you screened the peastone & only use what passed through a 3/16 screen but didn't pass through insect screening.

    Al

  • katskan41
    13 years ago
    last modified: 7 years ago

    From what I know of container gardening you could probably use the pea gravel in soil in place of the granite, as long as the pea gravel was fairly small and close to uniform size. Problem is that the pea gravel I've seen varies in size quite a bit within individual bags so as Al said above you should screen the gravel if you use it.

    I'm not sure it makes a difference when watering, as neither the pea gravel or granite absorb/release much water. I believe the larger the gravel the faster the water would flow out the container. Al can answer that, he's helped me a LOT with this kind of stuff. The smaller the gravel (1/4" to maybe 3/8") the better I think.

    I know the granite has sharp edges and gravel much rounder edges, but I'm not sure if the plant roots would care about that too much. Again, might be an Al question.

    I pay about $1.50 for a small bag of granite at the local feed store. They also carry 50# bags but I'm not sure of the cost.

    HTH

    Dave

  • libbyc
    13 years ago
    last modified: 7 years ago

    Hi everybody! I seem to be having a fertilizer problem. I posted on the FoliagePro thread, but haven't received an answer.
    I've been using the FoliagePro for a couple of months now, and I noticed a big difference between two containers, one of which has nasturtiums and bronze fennel, and another which has nasturtiums, ornamental oregano, and lemongrass. The nasturtiums in the latter container are lush and blooming well; the nasturtiums in the former container are scrawny, with yellow leaves and infrequent blooms, and the bronze fennel is dying at the tips. I know I was giving less FoliagePro fertilizer to the scrawny ones, but when I gave them more, nothing happened. Now I remember having given the pot with the oregano some organic fertilizer, 3-1-2 alfalfa meal. I sprinkled some on the scrawny ones and will keep you posted. I would note that it is VERY finely divided, almost a powder, so I'm hoping it will eventually go out through the screen on the bottom. I am watering all containers the same, and all drain well. I can put a finger down into the mix and just feel the barest moisture at the fingertip, and then I still don't water if nothing is wilting or it looks like rain.

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

    Same soil?

    You said you were giving one container less FP than another & it wasn't doing as well. My guess is the dosage you were using + the additional FP you provided was simply not enough.

    Al

  • katskan41
    13 years ago
    last modified: 7 years ago

    Just upthread there were a couple of posts regarding the use of granite vs. pea gravel in the gritty mix.

    I called the local feed supplier and a 5-pound bag of grushed granite (aka "grower's grit") costs about $1.50 and a 50-pound bag costs $6.00. The cost is quite reasonable compared to gravel.

    If you had access to both granite and pea gravel I'd personally go for the granite. As Al said both would probably work in the gritty mix but I've had good luck with the granite in the past and see no reason to change. The granite from the local feed store is fairly uniform in size and contains very little dust.

    I've read on several websites that sharp rock like the granite encourages fine root development and root splitting but I'm not positive that's true or not.

  • katskan41
    13 years ago
    last modified: 7 years ago

    When looking through this forum (and others on GW) I've noted that many list members ask about when to water their container-grown plants. I recall that Al (I believe) posted an answer to this a while back and suggested inserting a toothpick or pencil into the container soil and leaving it there for a few minutes to check for moisture. Basically, if the toothpick came out damp then there was probably enough water in the soil for plant use. If it came out dry, then the plant should be watered.

    In larger containers the top few inches of the gritty mix can be very dry but the bottom of the container can be fairly damp so I decided to use wooden skewers (the kind used for kebobs on the grill) instead of toothpicks. The skewers are about the length of chopsticks but thinner and have a sharp end. A bag of 100 skewers costs about $1.00 or so and can easily be trimmed to whatever length you desire. Most of my containers are less than 12" deep so these work great.

    Simply insert the sharp end of the skewer into the container soil and push it down until the sharp end is at or near the bottom of the container, being careful not to damage plant roots. After about 30 minutes or so remove the stick and check the dampness, then water if necessary.

    I keep the sticks in the containers all the time and check them every day or two, depending on the weather. Basically they work like an oil dipstick works in a car engine.

    If you have very deep containers then you'll need a longer stick but the idea would be the same.

    Just wanted to share this tip with the group.

    HTH

    Dave

  • buzzsaw8
    13 years ago
    last modified: 7 years ago

    ^

    Great tip Dave

    This is my first year using the gritty mix and it always looks dry from the first inch down. Sending wife to the Dollar Tree store tomorrow!

  • katskan41
    13 years ago
    last modified: 7 years ago

    Thanks buzzsaw but it's not my original idea. Al and others came up with the suggestion and I just modified it to meet my particular needs.

    I find its a fairly reliable gauge of dampness in the container soil, especially with the gritty mix. The top couple of inches of soil can be bone dry but down near the bottom of the container where the roots are it's still quite damp.

    Before using the wooden skewers I watered every couple of days because the gritty soil looked dry near the top. Now I find myself watering less frequently since I know the roots still have enough available moisture.

  • lathyrus_odoratus
    13 years ago
    last modified: 7 years ago

    Notice: I am not looking for help, simply posting something that others may empathize with or find as astounding as I do (we often assume that because someone specializes in something that they really know what they are talking about. I know that's not true, but still am surprised when it happens.)

    So, I'm still on the hunt for products I can use to make different soil mixes that are a bit faster than what I'm using now. I want to do some experiments both with wicking large containers and wicking small containers, like for small houseplants.

    I have a friend who works at a florist and I mentioned it to her. She said she works with many of the growers so maybe they would know where to find these products. Today she was over, so we called the grower she thought might help. This grower has been growing flowers in greenhouses for many years. Tracy called, explained I was looking for some things, then turned the phone over to me. The conversation went something like this.

    "Hi Betsy, thanks for taking time to take to me. I do mostly container gardening and am looking to change my potting mix" blah, blah. "So, I'm looking for the following things, pine bark...."

    "Oh, why don't you just use my mix?" Great! I think. She's got one already made with bark in it.

    "What's it made of?" I ask.

    "Well, it's all natural soil. We don't believe in soilless mixes, especially not in containers. I mean, how are plants going to get nutrients, especially the minors?"

    "Um, from a fertilizer that supplies the minors?" I offered.

    "Oh, but that's not the same. You should try our mix."

    "Thank you, but that's not what I want to do at this time."

    "But, all of our customers love it! You really should try it."

    I won't go through the rest of the painful call, but suffice it to say, she didn't have what I wanted, nor could she point me to someone who did. I'm sure I'll get them all eventually, but I'd much rather get them easily in one place since I mostly ride a bike and will have to borrow or rent a car to run this all down.

    Just hoping anyone else who's had problems with this might get a chuckle out of the story. And, also, pointing out how amazing it is that even people with a LOT of experience can know very little when it comes to science or research.

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

    The combination of complacence and 'experience' can be a dangerous thing. It leads to rigidity and a tendency toward a closed mind. I'm dealing with a person at another forum site now who laments that her soils are compacted and waterlogged, yet she resists any suggestions about how to relieve the problem while she clings tightly to the idea that more fine organic ingredients to 'feed the microherd' are the answer.

    My latest post pointed out that if she'd been more amenable to suggestion, she wouldn't have to suffer the source of her lament. It will probably anger her, but at this point, it's not an exercise in trying to educate her, it's more about those listening in to the conversation. Her combination of what she thinks is experience and a closed mind are very effective limits for her.

    Often, people think that they have seen improvement in their growing skills that they are at a pinnacle with no room for improvement. Often, the argument "It works for me" is offered as though it carries some kind of weight in a discussion, when all it really means is "I'm happy with the status quo and am willing to accept the limits any of my less than ideal practices have placed on me. One of the reasons I like this forum is because there seems to be a minimal number of participants with a closed mind - even if they don't agree with what I or others say.

    Getting back to the experience thing. If you do the same thing over and over again for 10 years, what 'experience' is there in that? Show me someone who has tried something 20 different ways over the course of 3 years, and I'll usually trust their judgment before that of the person with more 'experience'. Doing something wrong or inefficiently and simply declaring yourself content while refusing to consider other options is really not a big plus in the experience dept.

    Results are a subjective thing and what rings your bell may not be acceptable results as far as I'm concerned. The reverse could just as easily be true.

    Note: wherever I said 'you' above, it was the 'collective you' and not aimed at the previous poster. ;o)

    His post reminds me of something I wrote a while back on the Houseplants Forum. I might go looking for it & see if it's appropriate for this forum. I know it sparked considerable interesting comment there.

    Al


  • katskan41
    13 years ago
    last modified: 7 years ago

    Al and lathyrus that's a great thing to remember. Not everyone is willing to try new things or experiment with new ideas, especially when it comes to growing plants.

    I hope readers of this forum understand that anything I post here is only meant as a possible suggestion or alternative, like the posting above regarding the use of wooden skewers for testing soil moisture, or possibly growing container plants using only Turface. Under no circumstances am I suggesting that anything I post is the "only" way or the "best" way to do things. I learn by trial and error, just like everyone else.

    For instance, I've read both here on GW and other sites that some gardeners insist on using only organic fertilizers for their container-grown plants. Al and others have mentioned that using organic fertilizers in container soils may not be the best way to go due to a general lack of microorganisms in container soils and delays in organic ferts breaking down into usable forms. In spite of these issues some members still insist on using them, and I have no problem with that at all. To each his (or her) own I say.

    All we can do on these forums is come up with possible alternatives and suggestions for making improvements in how our plants are grown. If some members choose not to make changes and continue to use their current methods then it's their decision to make.

    As you can tell, I prefer to experiment with different soil mixes, fertilizers, etc. but I realize not everyone else wishes to do so.

    Thanks

    Dave

  • katskan41
    13 years ago
    last modified: 7 years ago

    Hi all. Over the weekend I opened up a fresh bag of Turface (actually Shultz Soil conditioner) and noticed that this particular bag has a fairly high percentage of fines. I only screened a small part of the bag but found that maybe 30% to 50% of the bag consisted of fines that passed through insect screen.

    I also noticed the particle color of this particular bag was more reddish/pinkish than the previous bags of Turface or Schultz I've bought in the past. Seems to work the same, just more fines and different color than what I'm used to.

    Besides using them for seed starting, what else can I do with these fines?

    I could add them to my garden soil or add them to planting holes when new trees or shrubs are planted as a soil amendment perhaps.

    Any other suggestions?

    Thanks

    Dave

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

    Don't add to planting holes. Current practice is to backfill planting holes with native soil only. I use the fines in hypertufa or mix them into my raised beds.

    Al

  • katskan41
    13 years ago
    last modified: 7 years ago

    Thanks for the tip Al. As always, you are a fountain of wisdom. =)

    Question: Do the turface fines absorb water just like the larger pieces of turface? I have not tested this yet but it would seem logical that they should absorb water as well as the regular pieces.

    I will use the fines and some grated sphagnum for seed starting and add the rest of the fines to our raised garden beds.

    Thanks!

  • shanielynn
    13 years ago
    last modified: 7 years ago

    I am trying to revive a long lost raised bed. Adding kitchen garbage, soil (from a store bought bag), and mixing (lots of mixing) with the sand. Could the fine/fines also help in this situation?

    Not too many choices to grow anything other than trees in our 'dirt'... Truck loads of garden soil would be required to recreate the raised beds that once were. I call it my sand patch experiment. Since I have such great luck with propagating succulents, I am hardening some off for eventual planting in the sand patch (it gets tons of sunshine). Our lot is completely surrounded by these old raised beds, and was wondering what to do with all of the teeny stuff left over (after all that sifting). Though hypertufa sounds pretty cool, might like to get my hands wet in that one of these days....

    You know, I do believe you will have to start another thread soon. Imagine that! Soil is such a cool (not hot =D) topic.

    Thanks as always,
    Shannon

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

    They would help only marginally, and not as much as OM. They have lots of internal porosity, and they hold water well, but their limited volume when mixed into a bed won't make a significant difference.

    Mmhmm - a new thread soon. Whooda thought soil was so interesting. Nerd alert! Lol

    Al

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

    Oh, BTW. I'd appreciate it if you guys would hold off on posting until I get a chance to set up the links to previous posts & can post it as the 150th to this thread. Thanks! I'll get to it later today when I'm finished at my REAL job.

    Al

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

    If you have interest, you can follow the link below to the continuation of this thread. Thanks for making this fun!

    Al