Home |
Search |
Today's Posts |
#1
|
|||
|
|||
CLAY SOIL (gypsum and pH)
"WiGard" wrote in message news This will alter the pH. Gypsum does not alter the pH of soil. http://www.awgypsum.com/why_use_gypsum.htm It does effect pH. The effect quoted here is called buffering, which is the tendency to modify excesses of high or low pH towards a middle value. The value depends on the type of buffer, for gypsum I think it is around neutral. To have a significant effect will probably take a great deal of gypsum and the closer the pH gets to neutral the less change adding more gypsum will produce. I would expect as buffering substances go gypsum would be quite a poor one. So while you are technically correct that gypsum _can_ alter soil pH but practically speaking if you wanted to modify soil pH you wouldn't choose gypsum to do it as there are much more effective ways. If you wanted to modify pH *away* from the buffer level, from neutral to either acid or alkali, you are completely wasting your time with gypsum. I would like to see this vendor produce figures showing how much gypsum would be required to raise the pH of a variety of common soils from say 5 to 6, which would be a typical sort of thing you would want to do. This is a complex issue. From the point of view of the practical gardener, if I had to choose between two simplified views of the world (1) "gypsum is useful to modify soil pH" and (2) "gypsum has no significant use in modifying soil pH" I would take the second every time. You should keep in mind that these people are trying to sell gypsum! David |
#2
|
|||
|
|||
CLAY SOIL (gypsum and pH)
"WiGard" wrote in message news This will alter the pH. Gypsum does not alter the pH of soil. http://www.awgypsum.com/why_use_gypsum.htm It does effect pH. The effect quoted here is called buffering, which is the tendency to modify excesses of high or low pH towards a middle value. The value depends on the type of buffer, for gypsum I think it is around neutral. To have a significant effect will probably take a great deal of gypsum and the closer the pH gets to neutral the less change adding more gypsum will produce. I would expect as buffering substances go gypsum would be quite a poor one. So while you are technically correct that gypsum _can_ alter soil pH but practically speaking if you wanted to modify soil pH you wouldn't choose gypsum to do it as there are much more effective ways. If you wanted to modify pH *away* from the buffer level, from neutral to either acid or alkali, you are completely wasting your time with gypsum. I would like to see this vendor produce figures showing how much gypsum would be required to raise the pH of a variety of common soils from say 5 to 6, which would be a typical sort of thing you would want to do. This is a complex issue. From the point of view of the practical gardener, if I had to choose between two simplified views of the world (1) "gypsum is useful to modify soil pH" and (2) "gypsum has no significant use in modifying soil pH" I would take the second every time. You should keep in mind that these people are trying to sell gypsum! David |
#3
|
|||
|
|||
CLAY SOIL (gypsum and pH)
On Sat, 21 Feb 2004 01:26:19 GMT, "David Hare-Scott"
opined: "WiGard" wrote in message news This will alter the pH. Gypsum does not alter the pH of soil. http://www.awgypsum.com/why_use_gypsum.htm It does effect pH. The effect quoted here is called buffering, which is the tendency to modify excesses of high or low pH towards a middle value. The value depends on the type of buffer, for gypsum I think it is around neutral. To have a significant effect will probably take a great deal of gypsum and the closer the pH gets to neutral the less change adding more gypsum will produce. I would expect as buffering substances go gypsum would be quite a poor one. So while you are technically correct that gypsum _can_ alter soil pH but practically speaking if you wanted to modify soil pH you wouldn't choose gypsum to do it as there are much more effective ways. If you wanted to modify pH *away* from the buffer level, from neutral to either acid or alkali, you are completely wasting your time with gypsum. I would like to see this vendor produce figures showing how much gypsum would be required to raise the pH of a variety of common soils from say 5 to 6, which would be a typical sort of thing you would want to do. This is a complex issue. From the point of view of the practical gardener, if I had to choose between two simplified views of the world (1) "gypsum is useful to modify soil pH" and (2) "gypsum has no significant use in modifying soil pH" I would take the second every time. You should keep in mind that these people are trying to sell gypsum! David Correct. I mean, because it says so on the Internet doesn't always mean it's so. Gyp does not truly alter the pH in clay, rather, it helps the particulate with cation exchange capacity, rendering the soil easier for nutrients to become available. As you or someone said, buffer to neutral. Nothing will raise or lower pH, permanently. I've used pellet gyp in clay and it is very effective, along with compost, in making soils friable when they are basically scraped off sub-soil, aka, second horizon. In Dallas, they scrape all top soil off, bag it and sell it back. |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Gypsum for clay soil | United Kingdom | |||
Gypsum Improving terrible soil in a lawn? | Lawns | |||
pelletized gypsum (to amend clay soil) | Gardening | |||
Gypsum and clay soil | United Kingdom | |||
Clay Clay and More Clay | United Kingdom |