1- thank you for info. 2- where do you buy this from. 3- don't get trapped, you can use Scotck Bright as cleaner, Or fine steel wool.

All those palms will grow well in clay soil. To improve drainage in clay, add up to 25% organic matter. There are many inexpensive moisture meters that are basically worthless. The VG-METER-200 - Soil Moisture Meter is a professional type meter that had good reviews when I researched it several years ago.

>>In their chart, more than 50% of the water is unavailable, but I have to think that is partly due to the depth of the sample beyond many plants' root system. That's specifically the water-binding capacity of the soil particles. Sandy soils don't bind water very tightly because they're large. There's plenty of room for water to hang out in the middle between them, essentially bound only by surface tension to the water that's closer to the particle. However, because of the large open spaces, not much water actually gets bound. The tension binding is too weak, and most of the water simply runs through, leaving air in the interstitial spaces. Very fine clays have tiny spaces and bind enormous amounts of water...but it's bound so tightly the root can't exert enough osmotic pressure to break the electrostatic binding to the soil particles. All things considered, most average roots can exert about an atmosphere of pressure to pull water away from the soil (or, they can pull as hard per square inch of area as a thirty foot column of water weighs per square inch of area, which is pretty hard). Clays bind water at greater than 1 atmosphere of pressure pretty easily. Sand, not so much. The storage limit is there to indicate what the soil can actually hold in its structure. Amounts of water above the upper storage limit simply drain away (eventually, anyway). Since soil doesn't hold vast amounts of water, the 100 cm basis is used to get good measurements and minimize the measurement inaccuracies. One meter seems about right for that, as well as being a cross section of soil that's relatively easy to handle. You also have to take into account whether the volume of root exposed to adequate water is enough to supply water to the entire plant. If the top three inches are too dry but the fourth inch is OK, the grass may or may not be fine. In very hot weather, I'd count on wilting--there isn't enough root system in the water to supply the whole plant. In fall or spring, wilting is less likely since water demands are so much lower. That stress, with adequate water at the low range, does send the signal that more roots are necessary. Or, why we always recommend deep and infrequent watering--the plant "knows" the lower roots have water, it's just not enough. For that reason, plants that may form six inch balls of root in the garden will fill an entire enormous pot on the patio. Garden water levels are usually adequate, patio water levels, not so much--and I always water until the pot pees, both to flush exuded waste products and to encourage the roots to go to the bottom. So yes, water stress will reduce as your roots deepen--and organic matter certainly helps! I wouldn't say the process is all that fast in either case, but year on year you should notice your watering dates spreading further and further apart.

On the subject of moisture meters: inexpensive 'battery free' meters will read '0' even when placed directly in distilled water because they are not measuring moisture but the difference in electrical conductivity between the two metals on the probe. You can try it yourself, distilled water has no salts in it so there is nothing to measure. Mine shows '0' with distilled water, '5' with tap water and requires adding salt to get it to show 'wet'. This is not your case because as you said your soil was wet at the bottom. You may have excessive evaporation on the high levels of the soil with insufficient water uptake from the lower regions. Maybe root rot, maybe the container is too large. If you do/did have root rot the lower roots are likely the ones to rot first because the bottom remains wettest longest. You can consider a fabric bag pot which will increase evaporation and will help the root zone dry out more quickly. I will leave it to others to indicate if re-potting a third time into a different type container is even a good idea at this point. Depending on the temperature differences between the root ball an the the "tree" portion this can contribute to slow water uptake. Measure the temperature of your root ball, a digital kitchen thermometer will work perfectly, and see what it is. Temperatures below 55F with a high amount of light can cause leaves to be water stressed (need water, cannot get it quickly enough, leading to drop off). It's worth noting again that depending on the kind of tree it is some leaf drop when moving from radically different environment conditions (high natural sunlight -> below freezing -> low light indoors -> high light indoors can stress the tree to drop its leaves. As long as the stressor is no longer present it will bounce back ------------------------ As for that article on peat, interesting, but I do not find the conclusions drawn by the author to necessarily follow from the evidence they laid out. Coconut coir (dessicated coconut husk) has similar aeration and wetting properties to peat, but is more "sustainable" (there is a large coconut industry and they need to do something with coconut husks). It holds onto more moisture and is not as acidic as peat based mediums however. FWIW: One commercial peat-based growing medium producer (Pro-Mix) recommends their peat/coconut coir/perlite mixture for trees/shrubs, another (Berger) suggests instead their bark based product. An obvious disadvantage of high peat based mediums is they dry out quickly in the hot summer sun by evaporation since they are so porous. Example: I grow tomatoes in 5gal paint buckets. In the hot (30C) July sun I need to water them every other day if the soil is uncovered. With a plastic bag on top the soil stays sufficiently moist for over 5.