Hi, rina. I know wood chips are different than bark, but I saw a nursery that was using these mixed with some alder saw dust. In about a year it turned to this incredible black, rich "soil". The guy as the nursery said it breaks down better and more nutritious for the soil and depletes less nitrogen in the process. The wood chips I was seeking are about the size of medium bark in nurseries. In retrospect, I am glad I didn't try that. Works great outdoors, not sure about containers! The black bark is essentially composted evergreen tree bark. I say evergreen because it could be a mix of a number of different types here in the Pacific NW --- hemlock, fir, ceder, spruce, etc. I didn't screen it, it seemed plenty loose initially; small to medium size in comparison to bagged nursery store bark. It would have been o.k. had I added the peat and perlite per the formulas given here. Screening would have left just the larger pieces, but that would be quite a chore for the volume I was using! I repotted some of the plants using the 5:1:1 formula with my black bark and those are doing much, much, better. A gardening friend said "Think of it...bark is like big saw dust. If you pack it down it gets as hard as a board". That is essentially what happened when I used the black bark alone without the the perlite and moss. ;(

Thanks for the kind words, B&C. In Mississippi, Memorial day would be a good target date for repotting the fig. Hibiscus need an annual repot. Do that toward the end of March, before it starts growing in earnest. Apple and most deciduous trees should be repotted just before or at the onset of spring budswell. Cactus - ask the cactus experts at the cacti/succulents forum. Desert rose - in Mississippi - June Umbrella plant - June There are ways to mechanically limit the amount of perched water a planting will hold, even if you're using a very water-retentive medium. Eliminating all or most of the perched water allows the grower to use media that would otherwise be or border on the edge of unusable. This outlines ways to cope with heavy (water-retentive) media Another effective way of dealing with media that hold too much water is through the use of ballast. You can read more about that technique here: Ballast ..... For now, checking your planting's moisture level regularly with a 'tell' will make a difference in your plant's appearance and level of vitality. Here's something I wrote about that: Over-watering saps vitality and is one of the most common plant assassins, so learning to avoid it is worth the small effort. Plants make and store their own energy source – photosynthate - (sugar/glucose). Functioning roots need energy to drive their metabolic processes, and in order to get it, they use oxygen to burn (oxidize) their food. From this, we can see that terrestrial plants need air (oxygen) in the soil to drive root function. Many off-the-shelf soils hold too much water and not enough air to support good root health, which is a prerequisite to a healthy plant. Watering in small sips leads to a build-up of dissolved solids (salts) in the soil, which limits a plant's ability to absorb water – so watering in sips simply moves us to the other horn of a dilemma. It creates another problem that requires resolution. Better, would be to simply adopt a soil that drains well enough to allow watering to beyond the saturation point, so we're flushing the soil of accumulating dissolved solids whenever we water; this, w/o the plant being forced to pay a tax in the form of reduced vitality, due to prolong periods of soil saturation. Sometimes, though, that's not a course we can immediately steer, which makes controlling how often we water a very important factor. In many cases, we can judge whether or not a planting needs watering by hefting the pot. This is especially true if the pot is made from light material, like plastic, but doesn't work (as) well when the pot is made from heavier material, like clay, or when the size/weight of the pot precludes grabbing it with one hand to judge its weight and gauge the need for water. Fingers stuck an inch or two into the soil work ok for shallow pots, but not for deep pots. Deep pots might have 3 or more inches of soil that feels totally dry, while the lower several inches of the soil is 100% saturated. Obviously, the lack of oxygen in the root zone situation can wreak havoc with root health and cause the loss of a very notable measure of your plant's potential. Inexpensive watering meters don't even measure moisture levels, they measure electrical conductivity. Clean the tip and insert it into a cup of distilled water and witness the fact it reads 'DRY'. One of the most reliable methods of checking a planting's need for water is using a 'tell'. You can use a bamboo skewer in a pinch, but a wooden dowel rod of about 5/16” (75-85mm) would work better. They usually come 48” (120cm) long and can usually be cut in half and serve as a pair. Sharpen all 4 ends in a pencil sharpener and slightly blunt the tip so it's about the diameter of the head on a straight pin. Push the wooden tell deep into the soil. Don't worry, it won't harm the root system. If the plant is quite root-bound, you might need to try several places until you find one where you can push it all the way to the pot's bottom. Leave it a few seconds, then withdraw it and inspect the tip for moisture. For most plantings, withhold water until the tell comes out dry or nearly so. If you see signs of wilting, adjust the interval between waterings so drought stress isn't a recurring issue. Al

Yes, I stated that I'm not worried about the aluminum, all the same I won't use aluminum sulfate either. Although it may be safe, I worry about toxic levels. Just because lead is in all soils doesn't mean it's a good idea to add more. Same with aluminum. And if you mix turface without a mask, you will be exposed to it. As far as water absorption Axis noted that turface holds 95% of it's weight in water. Pumice only holds 15% and DE holds 142% Try diatomaceous earth in your tests. Optisorb is about the largest size available to home gardeners. Axis makes an excellent size, but is for commercial use only. Numerous studies document it's use as superior to most other amendments. Such as " Effects of diatomite on soil consistency limits and soil compactibility" by Ekrem Lutfi Aksakala, Ilker Anginb, , , and Taskin Oztasa Or "Effects of diatomite on soil physical properties" by the same authors. Also "Sustainable effects of diatomite on the growth criteria and phytochemical contents of Vicia faba plants." Mona M. Abdalla* Department of Botany, Faculty of Science, Ain Shams University, Cairo, Egypt. The Axis company also has great info on all amendments. As far as particle size, do a test. Fill a pot with sand, and one with gravel. Stick a pole in, and see which one gives more resistance. It seems to me gravel would. But I might be wrong? I don't know physics well enough to figure it out on paper. Ah and pumice is further dashed to the ground and called a fake, not a single user rises to defend. Well we can agree to disagree, my day job is a laboratory researcher,or was, I'm retired. If turface has various pore sizes then it is not very well made. Thanks for pointing that out. So you do not believe the manufacturer? Controlling pore size in fired clays is often accomplished with the use of polymers such as Polyethylene glycol. This process is extremely important to control how well purifiers work, or how well they hold up with the addition of salts. You are incorrect about the pore size. Yes pore sizes differs, but that process is used to make different products, and is very controlled. Turface is meant to have small pores size or it would ineffective in it's intended use. The porosity of fired clays is extremely important to have a consistent product such as fired brick used to built houses. Varying pore sizes will compromise the strength of the brick. Selling a product and manufacturing one are very different things. The pore size I reported is for calcinated clay. Range of pore sizes is from .1 -.01 microns. Median is .045 . Plants need a .2 micron minimum pore size to utilize. This info is from a study by Andreas Kalytta-Mewes, Kathrin Mattern, and Armin Reller University of Augsburg, Chair of Solid Body Chemistry Georg Armbruster Soil Laboratory. The pore analysis in the study was conducted by Quantachrome,Bavarian Institute of Applied Environmental Research and Applied Technology. Of course it appears none of these sources trump Al. Who has not provided any data at all to back his claims. Please prove to me that pore size is bigger, thinking Al is right because you sell clay products is not proof. After saying all this will turface work? Yes, it will. Works pretty good! Is it ideal? No, it's not, but what is? It's still worth trying for sure. It didn't work for me, but that means nothing. it has worked well for others. It would be nice if it allowed easier access to stored water, but it does store water, and air, and it lasts a long time, maybe 20 years. That's decent. It's a decent product, or appears to be. It would not be on the market if it didn't work. I know it's not meant for potted plants, but it is meant for grass. DE seems a better product, it has it's own problems. it is marketed though for plants more than ball fields, although it is marketed for that too. It's marketed for large commercial gardens. I use it in my garden. I use turface too for my grass, works well. Just not that well in pots for me. All i said that it didn't work for me. Sorry blame me, it's what you usually do when the mixes fail, you blame the poster. Many have said DE doesn't work for them. I actually believe them. All gardening is local. This post was edited by Drew51 on Mon, Dec 29, 14 at 15:33

Over the years, I've saved a ton of word documents that answer common questions. One of those documents is about particle size: Particle Sizes (ideal) In a perfect world, the mineral fraction for use in the gritty mix would range in size from 1/10 - 5/32" (.100 - .156", or 2.5 - 4.0mm). The bark fraction would be slightly larger to allow for some breakdown over the life of the planting ........ from 1/8 - 1/4 is about ideal (.125 - .250" or 3.25 - 6.25mm). For the 5:1:1 mix, particle size should be from dust to 3/8". (0 - .375", or 0 - 4mm), with most of the bark ranging in size from 3/16 - 3/8" ( .188 - .375", or 4.8 - 9.5mm). The perlite should be on the coarse side - something like the all purpose or super coarse shown below. If you read the size gradation next to the images, you'll see the images are misleading as the product appears to be much larger than the size listed in print. starter: 1/16 - 3/32 inch (1.6 - 2.4mm) you can sub #1 cherrystone/quartzite if available grower: 3/32 - 3/16 inch (2.4 - 4.8mm) you can sub #2 cherrystone/quartzite if available developer: 3/16 - 5/16 (4.8 - 8.0mm) you can sub #3 cherrystone/quartzite if available turkey: 5/16 - 7/16 inch (8.0 - 11.0mm) turkey finisher: 7/16 - 5/8 inch (11.0 - 16mm) The last 2 sizes of grit can be used as ballast in the bottom of shallow pots by mixing 3 parts of grit to 1 part of your soil; this, to avoid water perching above the layer. The layer should be as tall/deep as the PWT your soil supports. Skip this if using a properly made gritty mix. Al