Karen Chapman co-author of Fine Foliage gave a lecture this spring and she stated her dislike for the gel polymers. Her idea is when your soil is dry and you have those in the soil they draw moisture from the soil, taking away water from the plants. She doesn't use them, she is a local container designer. I used them once but did't really notice a big improvement. When I plant a hanging container I use a small clear container saucer in the bottom of the pot. Holds just a bit of water like a reservoir but, I use moss lined baskets and they dry out really fast. Works like a charm.

I also tried the potting soil with the gel polymer crystals years ago. They stay too wet here, drawing on all the humidity in the air. Never really dry out. Might be ok in the winter, or for some really water-loving plants, but whatever it was that I had potted in that stuff died amazingly quickly, and it was obviously root rot from staying too wet, as I recall.

Rick, with your clay soil and living in the PNW where it rains a lot, I'd be worried that the crystals might not dry out, and could possibly make matters worse. Recommend you try a small, controlled experiment - maybe in a tub or big pot? - before you go for 10lb. of crystals. They're not cheap and might be impossible to remove once you mix them into an area of soil.

Compost has the same properties, in a cheaper, more natural and I think more effective form. Cellulose fibers swell up like tiny sponges when they get wet, and shrink to leave air spaces when they dry.

I don't know enough about the crystals but it sounds like you have had (bad) experience with them.

I have troubles with sun-loving plants getting too hot in the sun too. I don't think it was mentioned yet that the color of the pot can make a huge difference. A white pot will not get anywhere near as hot as a black or dark green one. If it gets too hot to comfortably put your hand on it, it's probably way too hot for the roots of most plants.

I also moved plants off of my deck, (in previous years, we moved this spring,) painted a not-terribly-dark shade of gray, but it would get too hot to walk on in bare feet. That's too hot of a place to sit pots.

Love to find spots where the pot can be in shade but the plant is in the sun, hard to finagle!

Yes, unless you sink the pots into the ground and hide the edges with mulch, Tiffany. I do this a lot because most of my yard is full of oak tree roots and many of my ornamentals just can't compete.

But if you've ever visited Epcot in Orlando, they do this all the time, and that's how they keep their gardens in full bloom and looking so perfect, and are able to change the plantings so quickly and easily. When one thing is in its glory, they fill a huge bed with pots of it, then when it starts to fade they replace with something else.

Putting the pots in the ground has a lot going for it. Lots of positives, few negatives.

springcolor said:Karen Chapman co-author of Fine Foliage gave a lecture this spring and she stated her dislike for the gel polymers. Her idea is when your soil is dry and you have those in the soil they draw moisture from the soil, taking away water from the plants. She doesn't use them, she is a local container designer. I used them once but did't really notice a big improvement. When I plant a hanging container I use a small clear container saucer in the bottom of the pot. Holds just a bit of water like a reservoir but, I use moss lined baskets and they dry out really fast. Works like a charm.

The gel polymers work fine in hot dry climates for containers. The important part is not to water the container from the top and let the water flow through the pot once the crystals have dried. They do create those air pockets Rick mentioned and the water just goes through the pot right past them and they do not have a chance to absorb water to be held in the container.

However, if you set the container in a drip tray overnight and allow the water to be absorbed through the base of the container they do perform the function of holding moisture in the soil for a longer period of time.

For me, this means I don't have to water container plants twice a day.

Smiles,
Lyn

RoseBlush1 said:

...the water just goes through the pot right past them and they do not have a chance to absorb water to be held in the container.

However, if you set the container in a drip tray overnight and allow the water to be absorbed through the base of the container they do perform the function of holding moisture in the soil for a longer period of time.

Now I know why I never had much luck using them - I always watered from the top. Thank you for sharing this information

Elaine,

You convinced me. "Usually too wet" describes my soil and climate perfectly. Also, when the soil DOES dry out (in the summer, a.k.a. "dry season") is when I don't really need improved aeration. The time I wish I had "channels" is during the 9-10 drizzly months.

I think I'll stick with my regular clay soil improvement plan:

1. As much compost as budget, time and energy allow. Scratched into the top 2-6 inches. Now that my compost heap is no longer a "weed seed factory", I can't make much of my own compost each year, so I have to buy it in bags.

2. Some gritty stuff mixed deep (coarse sand and grit once, then bark shreds every 3-5 years) .

3. Deep turning, screening, heavy amendment or soil replacement the very first year, then deep turning only when the clay washes out of the top few inches and turns the next few inches back into clay.)

4. Deep turning every 3-5 years

5. Grow something annual with deep roots occasionally.

6. (Maybe I should use up the rest of that bag of gypsum over several years, but I do NOT think I have excess sodium. With all the drizzle, I assume that anything soluble was washed out years before I moved in, and my additions leach out within a year.)

Rick, over the years we've improved our garden soil remarkably by (1) adding coarse sand one year (probably 8 years ago or so), and (2) mulching the garden every year with grass clippings from our lawn. I do make compost and that has certainly been a factor in improving the plant growth and health, but the sand and all those grass clippings (we have a pretty big yard) over the years have improved the drainage in the garden about a thousand percent. At one time we always had standing water in the garden when we'd get a heavy rain -- now there is none, even when the rest of our yard has huge puddles.

Rick, when you disturb the soil, you ruin the drainage and layers. Not at all necessary, or even desirable, to have 'good dirt.' Just keep adding OM to the surface, like mother nature does! I've seen this 'fix' heavy clay soil that won't ever dry and sandy soil that's never moist.

http://permaculturenews.org/20...

Going by "the soil triangle", even as little as 40% clay gives a soil that is "clay" (not clay loam). That agrees with my observation that sand alone doesn't cure clay, although I never bought enough coarse sand or grit to make a raised bed that was 60% sand and 40% native clay.

It also agrees with my observation that my clay remains AWFUL for growing until it is mixed with at least an equal volume of (compost + bark + sand + grit).

It also agrees with my observation that when I tried to rely solely on compost to repair clay, it only worked until the 50% compost decomposed. Like, for 6-12 months. The clay soil subsided and reverted to clay.

My understanding is that it is hard or impossible to get aerated warm soil to maintain more than 5-10% organic matter.

Maybe it is possible for continuously top-dressed mulch to maintain the organic content of a soil higher than the 5-10% I read about, but it would surprise me if that can keep the soil 18 inches down at a 50% compost level.

My guess is that the "OM-only" solution to clay soil works better when soil is merely poorly draining. Clay loam? 25-40% clay? Or maybe even relatively light clay soil, like 40-50% clay.

When the soil (sub-soil in my case) starts out more like 60-80% clay, I think it needs something in addition to OM to slow down the rate at which it reverts to totally unusable clay.

I know that many people, probably a large majority, have fixed their "clay soil" with compost-only, but I'm guessing they started with half of my clay % and used 2-3 times as much compost each year as I have.

I totally don't want to say that something that clearly works well for many people "doesn't work". All I really know is that there are procedures that worked for others that did not seem to work for me (or I never had enough compost to get the result I was seeking - soil that remains aerobic, friable and has tilth down 18-24".

In some of my beds, the soil was literally like modeling clay when wet. All of the beds were hard enough that a pick only chipped them when dry. It was a typical development: they bulldozed away everything soft and then sloped what was left so that water would run off (literally).

I know that many people are resolutely no-till. And it makes sense to me that, after soil is less than 40-50% clay, existing roots and soil fungi plus frost heaves plus worms plus insects plus aggressive top-feeding of OM ought to be able to keep it somewhat aerobic and draining. Hopefully deeper than 8-12".

After I improved some of my beds by a factor of 2-3, at which point it became like what most people call "heavy clay soil" as opposed to what the soil triangle calls "clay" I was able to go over to an infrequent-till policy.

When I dig down 18-24 inches, if I find sticky clay that looks like it would make an air-tight seal, I turn more compost under and think about buying another yard of crushed stone.

Rick, it sounds as if you and I have the same native "soil" - what we refer to as pure adobe clay (there is a reason they used this "soil" for missions) . 15 years ago, I had to do major double dig for the vege area and I added enough compost so that the end result was close to 60-65% adobe and 35-40% compost. 4 times a year on average, we add 8-10" of compost followed by several inches of mulch on top and, each time, it collapses down to less than an inch within 2 months (if it is warm outside). If I allow an area to sit fallow for a year and don't add the old barn pickins, the soil re-compacts as hard as a rock. So... although our soil is improving a little year by year, I definitely hear what you are saying.

>> I added enough compost so that the end result was close to 60-65% adobe and 35-40% compost. 4 times a year on average, we add 8-10" of compost followed by several inches of mulch on top and, each time, it collapses down to less than an inch within 2 months (if it is warm outside).

Yeah, that's what I'm talking about. Nasty stuff! Amazing that it is digested so fast despite the fact that it must be getting low in oxygen as it slumps down.

Sort of like a souffle that collapses if an ant stomps on the kitchen floor.

I found that adding even 10-15% coarse sand and crushed stone plus 20% shredded bark made the resulting pudding a little more "stand-up". Does anyone in your area have sandy or gritty sub-soil?

But I still had to "fluff it back up" every year or two, until some cumulative effect kicked in and moderate amounts of compost and bark maintained SOME slight amount of soil structure. It was as if residual roots were acting as a scaffold to support the pudding from flowing back into the pores I had created the year before.

Perhaps I should use the term "fluffing up" rather than "deep tilling". I use a long-bladed "sharpshooter" or trenching spade, plus a garden fork. I never deep-turn unless I have at least several inches of compost to turn under.

I would kill for 10" of compost and mulch, even ONE time per year!

It feels more like "whipping air into egg batter" than "beating the soil down with a roto-tiller".

I realize that my soil recipe is about the same as that for adobe mud bricks. I guess that part of the brick-making process is to squeeze air out and encouraging the ingredients to stick to each other with few pores.

My process is more like forcing as much air INTO the mix as possible, then firming it down gently, then watering very gently the first few times to try to "lock in" as much open space as possible.

Some of my deterioration is probably just "slumping" in addition to the oxidation of the compost. Getting more bark fibers into the recipe seemed to help.

It was very conspicuous that clay-plus-some-finished-compost would slump back into pudding very quickly, especially if at all damp. However,
clay-plus-some-finished-compost [/b]PLUS sand plus bark plus grit[/b] would not slump as much, as if the bark and grit made a framework like rebar, and the sand "dusted" clay balls so they didn't stick, and the sand "broke up" adhesion inside clay balls so they were friable with a rake and 1/4" screen.

Or I'm imagining the mechanism. All I rally know is that I kept changing my process and recipe until it started working better. But I would love to try again with 5 to 20 times as much compost as I've ever had at one time!

Rick and I have discussed this. My soil is the extreme opposite of his soil. ... My native soil is more small rocks/pebbles than real soil. It's perfect for drainage because the water drains through it quite well, yet the clay that is between the tightly compressed rocks does hold moisture unlike sandy soil.

It can rain hard for days and I'll never see a puddle. There are so many rocks I cannot dig in it with a shovel. It is not light and fluffy soil. Yet when plants are established ... and fed ... they do quite well in it pushing their roots through the crevices in the rocks both to anchor themselves and to seek moisture. When I was new working with the stuff, I knew there were no nutrients in the soil for plants because it wouldn't even grow weeds. I was such a novice, I tried to amend my planting holes with compost. HA ! So much for not understanding what I was doing. The compost decomposed and I was left with plants that sunk down into the holes I had dug for them. At that time, I didn't know I was supposed to prepare whole beds. Oh, well. The whole bed would have sunk ...

I went to no-till to save my back and my sanity. The interesting part is that no-till was/is the best method to work with this kind of extreme soil situation. What works in one place does not always work in another place.

Since we are in extreme drought, I didn't transplant the plants that sunk as planned this year into the beds I've prepared for them. Believe it or not, in the new beds I am using native soil ... clay .. cinder rock, gritty sand and some compost. I've let it sit for a year and it is quite friable. I think adding the cinder is what keeps the beds draining quite well. Again ... no puddles. The cinder rocks provide the air channels that enable the exchange of oxygen needed by the soil bacterial and worms. Pure clay with smaller particles seems to just turn into goo and does not allow oxygen to even get into the soil.

Yes, I do put compost and shredded leaves on top to decompose every year. It takes a long time to make soil like mine viable.

Smiles,
Lyn

Clay + sand = concrete. I wouldn't add sand to clay, or clay to sand. You want humus, tilth, decomposed organic matter, not clay, sand, rocks, or silt. The microbiologist explains it much better than I can (in link I pasted above,) without a bunch of jargon only scientists know.

When I lived in OH, I started many new beds in pure clay, in housing developments where they remove the top soil for sale, dig the basement hole, using that really deep solid clay to make a gentle slope from the house down to the street. Suck your shoes off when wet, cracked like the desert when dry.

By doing nothing more than covering the soil with tons of OM, especially leaves in the fall, after about 18 months, it turned from solid clay into almost black, spongy, fertile soil that was no longer muddy or baking dry.

Also seen it work in the sandy soil here in AL. I don't have to water stuff even if it doesn't rain for weeks & is 100 deg every day. I've been trying to use my excesses to landscape my Mom's yard the past few years, and in a few spots, DH couldn't dig with a shovel, he had to use a maddock to dig holes for plants. I piled leaves and mowed grass, small trimmings when working nearby, in a ring around them, and am noticing a difference already, since spring in some places. When I water it soaks down/in instead of running away sideways. The grass around these pots is making a bright ring where it's finding retained moisture still. Farther away from these newly planted spots, it's baked into dormancy.

We moved in April & when it cools back off, I'll start some new beds here, and will take pics from the beginning. If I didn't know how easy it was to make 'good dirt,' I would have brought dirt as well as some plants from old house. After 2-7 years (spots of different bed-age,) there's a lot of really really great dirt over there. Using free materials is all I need, nothing purchased from a store.

Tiffany ...

Thank you for sharing your experience. I have found that pure OM disappears in my hot dry climate. That may not be true in a more humid climate. I don't know.

Adding the cinder rock changes the texture of the soil and allows the OM I put on top to work. I can now use a trowel to dig in the beds to plant bulbs. I do know that OM plays a very important role in improving the soil.

Smiles,
Lyn

Tiffany, I agree that organic matter IS absolutely vital for creating or maintaining soil from almost any starting point.

Maybe with HUGE amounts of OM added to 80% clay, sand, grit and fibers are not as necessary as they seem to me. I've never had more than a few inches to add per season or per year, except for when I first made soil. Then, if I could afford 30-40% compost, it was a rare event. As I've mentioned, 12 months later, the (clay + compost + air mix) had reverted to clay + subsided bed.

The OM is vital for soil life as well as for soil structure, but you can GET BY adding only 5-20% OM per year if all you need to do is feed the soil life.

Even if someone makes some INorganic mix with good drainage and aeration, the lack of OM starves any "soil" organisms. That's hydroponics or soil-less gardening.

By the way, people with sandy soil who add only 10-15% clay can get good results, not concrete, but I suspect they already had or added "enough" OM to make it work. The voids and channels around coarse sand grains provide drainage and aeration, and even a little OM supports soil life and SOME soil structure.

P.S. My theory is that soil drains and admits air if the "coarse phase" supports itself with big open spaces between the clods, peds, pebbles, grit or coarse sand. Then the "fine phase" must be small enough that clay and silt never fill the open spaces, even after heavy rains and several years encourage the fine phase to migrate downwards and clog all the open space 12" below the surface. Also, if the "coarse phase" is some kind of an aggregate like clods or peds, they must not be so fluid that they "ooze" or flow into the open spaces and fill them.

I'm just offering that as a theory, not saying that what I've seen in my yard "prove" it. Something has to maintain open channels, and the rest of the soil can't completely plug those channels.


>> When I lived in OH, I started many new beds in pure clay, in housing developments where they remove the top soil for sale, dig the basement hole, using that really deep solid clay to make a gentle slope from the house down to the street. Suck your shoes off when wet, cracked like the desert when dry.

That does sound like awful, terrible, unusable clay soil. Somewhere between 50% clay and 100% clay. Once it is compacted, it might be difficult to tell the difference between 50% and 100% clay. Both are hard when dry and impermeable. Squishing it when wet might tell something, or using sedimentation to distinguish silt from clay might make it measurable.

>> By doing nothing more than covering the soil with tons of OM,

In my yard, I did not find that my clay + (moderate amounts of compost)
remained usable for more than 8-12 months. It rapidly reverted to pure anaerobic clay. To compare our results, I would have had to have bought 5-10 times as much compost as I did.

Also, maybe my first few years of compost was too "digestable". Compost containing (for example) coarse wood fibers or bark fibers acts like compost + sand or grit until the fibers decompose.

I need to go back, find that link and read what was in the link. But if a microbiologist wrote it, not a soil scientist, it probably dwells on the biological need for organic matter to soil life. I totally agree with that - 100%, not 90-95%.

Found it!

http://permaculturenews.org/20...

Yup, key words being "biologist", "biological" and "microbial life". I had seen one of her YouTube videos, I think the very one in that link.

Again, I agree 100% that soil (as distinct from hydroponic growing media) NEEDS organic matter to start with, and enough to be added every year to replace what was digested. Otherwise no microbes, worms or insects can grow in it, and plants' roots are much less healthy and effective (for example, because mycorrhizae can't thrive and penetrate plant root hairs).

...

Dr. Elaine Ingham

"Dr. Ingham is a world-renowned soil biologist who pioneered many of the currently used biological soil amendment techniques and pioneered the testing of soil microbial life as an indicator of soil and plant health. Dr. Ingham is the Chief Scientist at the Rodale Institute."

"Dr. Ingham is the key author of the U.S. Dept. of Agriculture’s Soil Biology Primer."

Just from my personal experience with our soil -- which I believe was a "clay loam" -- adding sand, although I do realize this isn't necessarily a recommended amendment, and then tilling in a LOT of organic material (our grass clippings, mainly) for a number of years, has totally changed the soil for the better. Originally there was barely a worm to be found, now a shovelful of soil reveals multiple worms (and, again, the soil has excellent drainage). This year was probably the first year (after 20+ years of having this garden) that I didn't till -- I normally till in the fall and we had a LOT of rain so it was too wet and I figured I'd just till in the spring; then we had a LOT of rain in the spring and I just said the heck with it and tidied the garden up with a hoe and rake -- most of the clippings, leaves, etc. that we had piled on in the fall, probably about 2' deep were decomposed except for a couple of inches of rough stuff left on top -- and planted. Where I was planting something like carrots I loosened the soil with my garden fork. Not sure right now if I actually ever need to till again, but I do think it's necessary in the earlier years of improving your soil. Just my opinion...

As a side note, our lawn doesn't look as good as a result of all that organic material being removed from it... but I don't care that much about that!