Container Soils - Water Movement & Retention VII

13 years ago

I first posted this thread back in March of 05. Six 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 participantsÂ 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 readersÂ growing experience.

I'll provide links to the previous five 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 ÂperchÂ (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 Â½ 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 Â½ 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.

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

Post VI

Post V

Post IV

Post III

Post II

Post I

Featured Answer

et14

13 years ago

last modified: 7 years ago

I have been reading to the point of being cross eyed. I have read the first 5 threads and half of 7. I have felt like this has been a boot camp on the subject. I just wanted to say thank you for your time and trouble. I started using your mix about two weeks ago and I have been amazed! The toms, peppers, squash and corn just seemed to have jump up a foot. Even the melons seem to love it. I modified the mix a touch by adding 1 part MG mix reg. to finish off the MG. Even with the rain here in central Va this weekend, the front steps has about 12 small pots with the mix for some more cucs corn and toms ready to go in the containers and the mix drained really well.

Sorry for the rambling, but I am really excited about this years plants. My grandfather has been gone for over twenty years he would have loved this. We had over an acre of garden when I was a kid and the good ole Al boy that he was, I can see him shaking his head and smiling.

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Comments (150)

libbyc
13 years ago
last modified: 7 years ago
I've been busy on the sunny days the past week and a half making up Gritty Mix. I made enough to fill my new black fiberglass square containers and a couple of pots, plus I filled up two trash cans with it for my neighbor. I used the Playball, the Gran-I-Grit Grower size, and pine bark that looks, size-wise, like a mixture of the stuff at twelve and three o'clock in your photo (I'll go to a quarry and dig sand, but I don't have the patience to sift four cubic feet of mulch!). I added the gypsum. I have already transplanted a Monarda. It is a tiny plant, but it seems to be already sending up more shoots. I had to maim my chives to get them out of their old pot, but they are doing fine in the Gritty Mix. Ditto the transplanted Coral Bells. I am using Miracle Gro Organic Choice dry plant food (7-1-2); I didn't want to waste the bag I had already bought, and I am going to grow some herbs and nasturtiums that I know need less food. I just received the shipment notice for the plants I ordered online; it's exciting! I'll probably have to keep them indoors a couple of weeks before transplanting. We'll see how it goes.
tapla
Original Author
13 years ago
last modified: 7 years ago
;o) Good luck, Libby!

Al
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filix
13 years ago
last modified: 7 years ago
Hello Al. If you were looking for bark fines, and you had a choice to have the real fine bark that passes through an insect screen in there. Or get it with the very fine stuff removed. Which would you prefer? Thanks. filix.
tapla
Original Author
13 years ago
last modified: 7 years ago
For the 5:1:1 mix, I'd prefer no more than a 10% presence of extremely fine material if I'm using peat. If I eliminate the peat, I think up to 20% is a good guess.

I never measure these things any longer. I just look at a handful of the bark & know by instinct how much peat to add, or if I should add any at all. It's not that technical. As long as you proceed with the thought in mind that your goal is to provide and protect aeration for the life of the planting, you'll be fine.

Al
filix
13 years ago
last modified: 7 years ago
Thankyou Al. I bought 3 yards of a mixture of composted bark and uncomposted. The Guy mixed it. After I sifted alot of it through 1/4 inch screen, there seemed to be alot of very fine stuff in it. And I was right. about 30 to 40 percent. So I made a screen gage. It has a wooden hatch. It's about the size of a moniter heater. It holds about 15 gallons of bark. Then I use my leaf blower to just blow the fines out. Thats when I noticed after blowing the fine stuff out through the insect screen there was about 1/3 gone. filix.
deep_roots
13 years ago
last modified: 7 years ago
Located gran-i-grit at $5.25 for 50 lbs and turface all-sport at $13.70 for 50 lbs. Too bad this stuff isn't lighter. Just thinking about the 50 lb large container that I am considering. ;)
kimcoco
13 years ago
last modified: 7 years ago
So fine bark pines is really nothing more than shredded mulch? If so, I have to sit here and laugh at myself hysterically as I was thinking this was some specialty item. I look at it every time I go to the darn garden store, for crying out loud. I SHOULD have read these (long) threads sooner. Tell me if I am wrong.
filix
13 years ago
last modified: 7 years ago
Your not alone kimcoco. It's the way it's worded. When you talk about sand that's fine, you don't say sand fines you say fine sand. for this stuff, it's bark fines. I'm so grateful for Al teaching me how to make this dynamite soil. filix.
tapla
Original Author
13 years ago
last modified: 7 years ago
KC - It might be a fine point, but I don't like the word shredded, because there are many other bark products out there that ARE shredded that are inappropriate. I think pine bark is chipped or ground if it's fine enough, but yes, pine fines are either chipped fresh pieces of large mulch or the same pieces that have been windrowed and partially composted.

Al
Aariel
13 years ago
last modified: 7 years ago
Hello again - I've just acquired some bromeliads, and am wondering about what type of fertilization they like.
linchat
13 years ago
last modified: 7 years ago
Pine Fines sizes?

I know it has been posted here but I could not search to find it. I picked up soil conditioner (pine) and the sizes are fairly small. Their is no "chunks" in the soil. I would say the pine are more like really light organic soil. Fluffy is the best description :) Probably around 1/8 inch in size for the most part.

I have tomato's in the mix right now (5:1:1) that are doing OUTSTANDING! I should repost the pictures that I posted to this forum earlier as the pictured tomato plants in 511 vs the pictured tomato plants in alternat soil have probably tripled in size and a ton more leaves.

So the plant appears healthy and loving it. Ultimately, are smaller pines OK or will it cause problems in the container?

Thanks.
tapla
Original Author
13 years ago
last modified: 7 years ago
Aariel - as I understand broms, there is a wide variety of nutritional needs that varies by species within the genus. Some plants like only occasional doses of N along with a fairly steady diet of 0-10-10, and others are perfectly happy with any 3:1:2 or 2:1:2 ratio fertilizer. Sometimes the fertilizing strategy takes into consideration plant shape/color, etc, and not just maximizing growth. I think I don't know enough about it to give specific advice, and it's probably outside the scope of the thread subject. ;o)

Linchat - It sounds like you have a source for your bark that is just perfect. ;o) I'm glad your plants are doing so well, too! Way to go!

Al
kimcoco
13 years ago
last modified: 7 years ago
Al, I feel like I'm beating a dead horse here, but here goes...

I have the formula for your gritty mix and your basic mix. Is there a general rule to know which mix to use?

So the gritty mix, equal parts, I'm using for my houseplants. Correct me if I'm wrong.

I have a rubber tree plant, not sure of the scientific name, but would you recommend the gritty mix for that as well?

And the other basic mix 5:1:1 I'm using for my outdoor container plants - mostly annuals - and my outdoor flower window boxes?

What mix do I use for my tomato plants (in containers)?

I'm putting in a new hosta bad up front this year, in full shade, do I amend the soil up there too? It's clay maybe 18 inches down, full shade, maybe a little on the dry side because all the mature maple & elm trees on our street.
tapla
Original Author
13 years ago
last modified: 7 years ago
Basically, I use the gritty mix for my woody material I'm growing on in containers (mostly for bonsai & I want rapid growth), houseplants (especially good for succulents and cacti/bulbs), and anything else I know will be in the same soil for more than a year.

I use the 5:1:1 mix for plantings intended to last only a year or two - veggies and the dozens of herbaceous floral display containers I place about the decks & gardens each year.

I use the 5:1:1 mix for tomatoes & all veggies (herbs go in the gritty mix).

Rubber tree/plant is prolly Ficus elastica, though there are other plants with the common name 'rubber plant' or 'rubber tree'.

I wouldn't amend the clay unless you can drain the water away to avoid the 'bathtub effect'. You might build a raised bed atop the clay, but again, I wouldn't double dig or incorporate 'drainage material' in the clay for fear of creating a 'bowl' that will fill with water each time it rains or you irrigate heavily. Hostas are pretty hardy & I've often seen them doing well in clay.

If the clay is 18" under the topsoil, go ahead and amend your heart out. ;o)

Al
kwyet1
13 years ago
last modified: 7 years ago
OK....I have made a 'big batch' of this mix because I have a couple of pots where my plants have rotted due to moisture retention. But, I also have lots of 'self-watering' containers. I'm thinking I should NOT use a 'rapidly' draining mix in the SWC???? Could I use it there also???? (If not, what DO I use???) Advice please....
Thanks,
Linda
tapla
Original Author
13 years ago
last modified: 7 years ago
Just increase the peat to 2-3 parts (5:2-3:1, PB fines:peat:perlite) or add a little vermiculite (5:2:1:.5, PB fines:peat:perlite:vermiculite). Note the decimal point before the vermiculite (.5) - that's a half part.

Al
justaguy2
13 years ago
last modified: 7 years ago
I'm thinking I should NOT use a 'rapidly' draining mix in the SWC???? Could I use it there also????

Linda,

If you are using 'official' Earthbox methodology where you have a fertilizer strip on the surface, or just barely under the surface of the potting mix and you have a cover over the top then you may need to use more peat or some vermiculite in the 5:1:1 mix to have the water wick fast enough to the surface and keep the fert strip moist. Same thing applies if you are direct sowing seeds into the container instead of transplants. The idea is that using EB methods, it is important that the top inch or two not stay dry.

If you are not following EB methodology and simply have a plant in a SWC and are fertilizing by incorporating a fert into the planting mix or using water soluble ferts in the reservoir or top watering them in then the 5:1:1 mix will work just fine.

If the bark you are using is fairly large and not at all composted you may still wish to increase the peat slightly. If it is somewhat composted you likely won't need to.

These days there are a lot of SWC designs on the market, some of which I have no idea how they even work. One design seems to expect the reservoir water to evaporate and the vapors soak into the bottom of the mix. Others use wicks or capillary mats. Others use wicking chambers where a small portion mix is in direct contact with the water.

Because of this some experimentation will be necessary to determine what works best.

Personally I only use SWCs where a portion of the mix is in water and wicking occurs from there. In my Wisconsin climate I use 4 parts pine bark (partially composted) and 1 part Turface MVP. No peat at all. I don't use EB methodology so I don't care that the top inch or so of the mix will be bone dry in the summer. In the past I have used the 5:1:1 mix with bark that was very fresh and not at all composted and did follow the EB methodology. I needed to increase the peat by 1 part or so for that to work.
filix
13 years ago
last modified: 7 years ago
Al I have a 15 gallon container with the gritty mix. The clem is doing well, but the pot is very heavy. I was going to try bark,DE, and perlite. For the weight. Will this be ok. is that too much perlite? filix.
tapla
Original Author
13 years ago
last modified: 7 years ago
It should be ok, Filix. The DE holds LOTS of water.

Al
kwyet1
13 years ago
last modified: 7 years ago
Thank you Al & justaguy2 for your responses...you both say to add vermiculite so I guess I will do that...maybe a little peat (the only pine bark fines I could find was partially composted)...As far as my containers, I have 1 'official' Earthbox...2 cont. from Gardenweb (all 3 rely on 'moisture wicking soil'), and 1 that has 'wicking material' on the bottom (plus I plan on making a few that I have seen on GW...they will be the 'soil wicking' type. Last year, I had 'forgotten' about the 'fertilizer strip' and had mixed it into the soil instead. Which way would work better for the container mix. Thanks so much for your responses!
Linda
justaguy2
13 years ago
last modified: 7 years ago
Last year, I had 'forgotten' about the 'fertilizer strip' and had mixed it into the soil instead. Which way would work better for the container mix. Thanks so much for your responses!

If you can put the strip of fert where it stays moist and away from roots that would be best (minimizes potential for root damage from high salt concentrations near the root), but the official EB methodology used to be mixing it in years ago as I understand from another poster.

I haven't done any kind of testing or comparisons between the two approaches so can't really help any further in that area.
esteban_2009
13 years ago
last modified: 7 years ago
I am unable to find two of my post from 2 days ago.
I asked questions about inverted soft drink containers for watering my 5 gallon containers. I got two wonderful answewrs that really "saved my bacon".
This note is to thank the two that responded.
Steve
tapla
Original Author
13 years ago
last modified: 7 years ago
That's cuz you're lost.

Al
terrace.newbie
13 years ago
last modified: 7 years ago
I'm running low on the bark fines but haven't seen them anyplace local. Does anyone in New York City (inclusive of Brooklyn, Queens, Manhattan & Bronx) know of a place where I can get them? Or someplace local enough that delivers to NYC? Mail order?
linchat
13 years ago
last modified: 7 years ago
I have got tomatos in 511 mix right now that were doing fantastic. They were fertilized with Espoma Tomato Tone. Long story short, they have started to take a turn for the worst. I suspected possible Magnesium deficiency.

Wandering what others are using for fertilizer? Do other people have Problem with Mg or Calcium deficiency in 511 and is it something generally need to stay on top of?

Symptoms are dried flowers, brown crumbing leaves, green veins with light color in between. Leaves seem kind of small and leathery. This is happening on two different varieties and at about the same time. Planted in 15 gallon containers. Happening to Better Bush and Better Boy variety.

Also, have been giving them Seaweed Emulsion / Fish Emulsion mix every couple of weeks. Is it possible heat problem?
justaguy2
13 years ago
last modified: 7 years ago
Did you add dolomitic lime to the mix? If so you aren't likely seeing a deficiency of Ca or Mg.

How much Espoma Tomato tone did you give and is this a top watered container or self watering container?

The Seaweed/Fish Emulsions aren't good choices in containers.

Please provide more specifics and if you can a pic.
linchat
13 years ago
last modified: 7 years ago
Will send pic this evening. I do not remember how much, but it was something like 1:25 as package recommended. I probably needed to fertilize again, I am over a month and the package recommends fertilizing again after 1 month.

Also, it is top watered via drip system.
linchat
13 years ago
last modified: 7 years ago
Here is 1 pic and 4 links to other pictures.I linked them in, did not want to display the pics and slow this LONG forum down. :)

This was to tomato in 511 which WAS doing stellar until its quick descent. I know it is something I have done, some kind of definiecy, but what?

And I did add dolimitic lime to the 511.

{{gwi:15159}}

{{gwi:15159}}
esteban_2009
13 years ago
last modified: 7 years ago
In the soil recipy, it calls for micro-nutrients.
In one post, Al mentioned Micromax, is that a Miracle-Gro product? If so, I can't find it in any of our local big box stores or in any of the local nurserys. Scott's still haven't answered my e-mail. I have checked into Earth Juice' Microblast..nothing local and the shipping cost will be prohibitive.
Does anyone have any ideas what I can do to get the needed Ca,Mg and S
Thanks again, this is a wonderful group.
Steve
tapla
Original Author
13 years ago
last modified: 7 years ago
Linchat - it looks like too much fertilizer to me. What did you use? How much? How often?

Steve - if all you're looking for is Ca, Mg, and S, you can get that with dolomitic (garden) lime + elemental S or gypsum + Epsom salts - (CaSO4 + MgSO4).

Contact me off forum about a micro-nutrient source.

Al
linchat
13 years ago
last modified: 7 years ago
Well stated off with Espoma tomato tone. I might have come buy and gave them some seaweed emulsion / fish emulsion. Anyhow, I just game them some miracle grow, well I probably just killed them.

I have two other plants in same mix with 9 month fertilizer, they are actually flowering nicely. I might have used garden tone on these plants and not tomato tone.

Oh well, try try again.

AL:
When you are talking about a Micro Nutrient source, the ferts I am using Mg, Ca, Copper and so forth. Is this what you mean instead of just NPK?

Or some with trace minerals as well? Is this what Micromax supplies? I am in the same boat as esteban_2009 none of these items are available in my area.
tapla
Original Author
13 years ago
last modified: 7 years ago
First. it wasn't a trace element problem that caused your plants to collapse. It was probably over-watering or fertilizing.

Most soluble fertilizers contain NPK, Z, Fe, Mn, and sometimes Cu. Primarily lacking are Ca, Mg, and S. Sometimes B(oron) or Mo(lybdenum) deficiencies will show up.

You cover the Ca and Mg with dolomitic lime when you make the soil. MG fertilizer & most solubles contain at lease the ingredients I listed above. S is usually very low in bark or peat based soils, so it can be a problem. To be on the safe side, I either add Micromax to my soil when I make it, or if the planting is in it's second or third year, I'll include STEM in the fertilizer solution.

The easy fix is to lime your soils when you make them and use Foliage-Pro 9-3-6 and forget the micro-nutrients. It contains everything essential to plant growth. For the gritty mix, you use gypsum instead of lime & then include a small amount of Epsom salts every time you fertilize.

Al
libbyc
13 years ago
last modified: 7 years ago
There is no frost in the ten-day forecast in my area, so I decided to pot some replaceable plants in my big 22" square container: purple basil, bronze fennel, and nasturtium seeds. I'm holding the Thai basil, Vietnamese coriander , and lemongrass until after the frost date, but the cats love the lemongrass, so it's a race to see if the cats get it before frost might. Although the purple basil was a little dried-out when I set it in, it perked right up and looks good. I sprinkled a very small amount of the chicken poop fertilizer on the mix, because I know it isn't the right ratio and the nasturtiums won't flower if treated too well. I have some 3-1-2 alfalfa meal on order.
Bee balm doesn't like being transplanted at all! My first sprig did nothing; the second bigger one promptly died. I think I have enough plants already anyway.
One coralbells bud drooped and died, but the other three look good. I'm thinking of getting a tall narrow trough-like container to put behind the herbs this fall, and growing beets in it in the cold weather and small eggplants in the summer. Hubby doesn't care for eggplant, so every time I buy a big one it goes bad in the fridge. I like the idea of picking a small one every now and then and enjoying it myself.
ragtimegal
13 years ago
last modified: 7 years ago
Hi Al,

Well, here I am- finally ready to mix up the 5:1:1. After much hunting, I have the products, though I am going to have to make some modifications.

My first purchase of fines is a Microbark, which turned out to be a little more coarse than I would like and appears to be uncomposted (the bag does not say). I then found a thoroughly composted product, Turf-N-Tee, and after picking it up today, it looks almost like it's a bit too fine. SO, in making do with what I have, I figure I will make a mixture of the two to comprise my pine fines component, and I've got the perlite, peat moss and Agricultural lime for the rest.

Here is a pic of the two ingredients.
{{gwi:15162}}

Do you think that the smaller particle size material is too fine, and if so, would my idea of mixing these two mediums work? I need approximately 10 gallons of the pine fines per container, so I'm thinking perhaps 4 gallons of the larger pieces mixed with 6 gallons of the finer mix. (No science there, I just pulled that ratio from thin air.)

Thanks!
ragtimegal
13 years ago
last modified: 7 years ago
Oh, and one more question- Can I use a layer of the microbark on top as mulch in the container or should I get something larger that resembles more of a shredded type of bark?

Thanks!
buzzsaw8
13 years ago
last modified: 7 years ago
Al or JAG - when adding gypsum to the gritty mix, does it need to be pelletized? I'm assuming yes, the powder form would just leach out? TIA
penfold2
13 years ago
last modified: 7 years ago
The lime/gypsum does not have to be pelletized. It will turn to powder as soon as you water anyways. You can observe this by just dropping a few pellets in a glass of water. The pellets just allow the material to be thrown more predictably when used outdoors and with spreaders.
esteban_2009
13 years ago
last modified: 7 years ago
Woe is me!
After mixing three 5 gallon containers of the 5:1:1: mix I realized I was using medium peat, NOT sphagnum peat. The peat I used this morning was very fine, like sawdust.
Would you folks recomment dumping all three containers out and starting new or is there a way to salvage my mistake.
Thanks,
Steve
aliceinvirginia
13 years ago
last modified: 7 years ago
I think the earlier problems I was having with the 5-1-1 was that a decent part of the pine fines contained larger pieces. I have a different brand of pine fines in an unopened bag.

Since I've got a large amount of pre-mixed potting mix with the larger stuff, is there any way to screen it out after the fact?

And what would you recommend using for a cheap sifter? Don't really want to go out and buy a thing of hardware cloth. I've been looking at the Dollar stores to see what kind of strainers they carry.

I've found a couple decorative baskets with painted mesh. Are those completely unsuitable?

Something I tried earlier with my potting soil comparison may be relevant to this discussion.

I was short on the commercial potting soil I used for my comparison, so I ended up covering the top with part seed-starting mix, part regular ingredients.

Since that stuff holds moisture pretty well, why not use it when planting seeds in the pine fines mixture?

If you have a 10 inch container, why not mix a little seed starter mix into the top inch of the 5-1-1. If you are top watering, at short intervals, that should keep the top layer relatively moist.

I'd add the caveat that I am doing this for veggies that I am growing from seed.

My unscientific take is that depending on the temperatures and soil moisture, some things (mostly observed lettuce) germinate quickly but don't take off growing rapidly in a loose mix like Al's mix.

I think I'm getting better results for plants that are in larger containers, grow relatively big and handle periods of drought better.

I still haven't figured out the right way to water with Al's mix. I'm used to sticking my finger into the plant, and if the top inch or so seems dry, I water. Plants that are physically harder to get to get watered less too. Particularly when I have a lot of them to water.

When my mom was really into gardening, she would get up to around 100 houseplants before she started killing them or giving them away. I think my limit of container plants might be more around 10 or 20. Depending how thirsty, fussy about water and fertilizer, and whether they are small and located next to each other. Such is the life of an apartment dweller with a demanding job.

Alice
tapla
Original Author
13 years ago
last modified: 7 years ago
Sorry guys - I've been 'away'. ;o)

I think I answered some of these questions via email, but if I missed you & you need an answer, please ask again. I know I didn't answer Alice, so:

You can buy small pieces of hardware cloth and insect screen at most good (real) hardware stores. If you have someone to make a frame from 1x4s for you, you can staple it to the bottom of the frame. You can sometimes find wire mesh waste-baskets & letter boxes (like for your in and out trays on your desk) at dollar stores or office supply stores/depts. They will be somewhat useful.

Seed mixes need to A) be sterile B) hold enough water w/o being soggy C) hold LOTS of air. If you can find any material that isn't toxic and meets these three requirements, it will work well as a seed starter. I use screened Turface, then layer the seeds and cover them with about 1/4" of Turface fines. If you have really important seeds & want to get them off to a REALLY goods start, mix a fraction of chopped sphagnum moss (not peat) into the Turface & it will REALLY give the seedlings a boost.

"My unscientific take is that depending on the temperatures and soil moisture, some things (mostly observed lettuce) germinate quickly but don't take off growing rapidly in a loose mix like Al's mix."

I find the opposite. There is no substitute for a very well-aerated mix to promote rampant growth in seedlings. Aeration is a key consideration in EVERY commercial from-seed operation.

From another thread, Les asked:

"If you would so kind as to answer a couple of questions for me - will orchid bark work in your 5-1-1 mix? Also, what would be the best way to water? it should be very hard to over-water in your mix - right? How and when to fertilize and at what p.p.m.?"

Orchid (fir) bark is generally too large and is uncomposted, but if it is ground fairly fine (1/16 - 3/16 is best) it will work. I usually use it in Water when plants need it - just before you think they will show signs of wilting. You need to water newly established plantings a little more often because roots are in the top part of the container, but once the planting is established & roots have colonized the soil mass, you can feel the soil at the drain most plants) and water when it feels dry. Alternately, stick a wick in the drain hole & water when the wick feels dry. You're right though; if the mix is made the way I make mine, it is very hard to over-water; but you CAN do it .... if you work hard enough at it. ;o)

Fertilizing is difficult to advise on, unless I know what you're using. If a soluble product like MG or others, there are a number of ways to fertilize. You should base application rates & intervals on temperatures & how fast the plant is growing. If you fertilize at 1/4 recommended strength every other time or every third time you water, while the plant is growing strongly, you will be in good shape. Alternately, you can half the recommended dosage and interval suggested on the container, or fertilize according to directions. If you have more fertilizer questions,l follow the link I left below.

Al
rj_hythloday
13 years ago
last modified: 7 years ago
It must be getting near time for VIII! I've read this one, and most of I. still a lot of reading to go through, but have on ? for Al.

In some of your comments you state that your containers are very quick draining and need watering daily.

Do you really water daily? Or is it just well drained? I find it a chore to water weekly, and I know you have a lot of trees in containers.

For my inground tomatoes (Open bottom SFG) weekly watering is supposed to be optimum. I get so much rain I don't know if I'll even water them at all this summer. If at day 7 rain is forecasted in a day or two I'd probably just hold off. I realize gritty mix isn't ideal for toms but wonder how often container gardeners are watering them.
tapla
Original Author
13 years ago
last modified: 7 years ago
When I pot a plant something in the gritty mix, I consider how much it will mature before I repot and how large the container is. I then guess at about how fast the soil needs to be so that the planting will go 2 days between waterings if it has to, once it has matured. This is really kind of automatic by now, but that's how I judge how to make the soil, and I do water ALL of these plants every day. Sometimes it's only a splash to get them through until the next day (commonly with the pines & junipers I'm growing on for bonsai, and cacti/succulents, which often go quite a bit longer than a day between drinks.

Stuff in the 5:1:1 mix gets watered as needed, but by the time summer is getting old and the plantings are mature, they almost ALL need a drink-a-day, too.

The short version is I come much. much closer to watering everything every day than I do to watering every other day or at longer intervals.

I actually start out with the basic gritty mix & amend it for each individual planting. The 5:1:1 mix is usually pretty consistent, but IU sometimes add a little something to that for particular plants, too.

I have found that the soils/plantings in containers that need more frequent watering are almost certain to grow at closer to their potential genetic vigor than those combinations that see extended intervals between waterings ....... as long as you don't forget to water and kill them. ;o)

Al
ditnc
13 years ago
last modified: 7 years ago
Al, for the big and small batches for which you provided the 'recipes', what is the total volume that results (in cubic feet or gallons)? Thanks.

"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)"
pat_123
13 years ago
last modified: 7 years ago
I'm not Al, but the small batch recipe above totals approx 4 gallons and for me will fit in one 5-gallon bucket.

HTH
tapla
Original Author
13 years ago
last modified: 7 years ago
The big batch makes from 3.0 - 4.5 cu ft of soil, or 25-35 gallons, depending on whether you start with 2 or 3 cu ft of bark.

The small batch, as Pat noted, makes about .5 cu ft or 4 gallons.

The Red Wings rock! ;o)

Al
ditnc
13 years ago
last modified: 7 years ago
Thanks Al and HTH!
rj_hythloday
13 years ago
last modified: 7 years ago
HTH = hope that helps 8~)
tapla
Original Author
13 years ago
last modified: 7 years ago
I'm going to repost the thread later tonight & will want to leave links in the last (150th) post. I would appreciate it if you would refrain from posting until the new thread is up. Thanks. ;o)

Al
tapla
Original Author
13 years ago
last modified: 7 years ago
Thanks for being patient, you can find the continuation of this thread by following the link below.

Thank you all very much for participating & making the thread such fun.

Al

Container Soils - Water Movement & Retention VII

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