I found this while searching for info on CEC. It was another subject I had been researching to get a better understanding of. As is often, when it is discussed on here, I am very slow on the uptake and further research helps me to better comprehend. So for those who may be interested in the Calcium/Magnesium relationship, hope this helps. JaK It's still a little-known fact that the Calcium to Magnesium ratio determines how tight or loose a soil is. The more Calcium a soil has, the looser it is; the more Magnesium, the tighter it is, up to a point. Other things being equal, a high Calcium soil will have more oxygen, drain more freely, and support more aerobic breakdown of organic matter, while a high Magnesium soil will have less oxygen, tend to drain slowly, and organic matter will break down poorly if at all. In a soil with Magnesium higher than Calcium, organic matter may ferment and produce alcohol and even formaldehyde, both of which are preservatives. If you till up last years cornstalks and they are still shiny and green, you likely have a soil with an inverted Calcium/Magnesium ratio. On the other hand, if you get the Calcium level too high, the soil will lose all its beneficial granulation and structure and the too-high Calcium will interfere with the availability of other nutrients. If you get them just right for your particular soil, you can drive over the garden and not have a problem with soil compaction.
Hey, thanks for posting this. I found the info useful. My mix is ca heavy and it does now have a slippery oiled feel to it and it's uniformly granular looking and isn't clumping... i actually thought it was good that it was easier to mix of late. I added way too much of the oyster shell flakes that i bought.
skunk, glad it helped you out. I have been coming across so much stuff out there to get insight into nutrients/soil/minerals and am actually starting to understand the balance needed to get a good soil going. A lot to learn, that's for sure. I started out wanting to just have s simple grow, but finding the science of this very interesting. Always nice to cultivate the brain, too, right? JaK
JaK One thing to keep in mind when looking at a plant's nutrient requirements is to consider everything that you're adding. Yes - calcium is probably one of the most important components in a good soil. Fortunately it's everywhere - kelp meal, alfalfa meal, (basically any plant-based amendment), crab/shrimp meal, neem seed meal, et al. Earthworm castings are covered with calcium carbonate (CaCO3) - the good form. Concentrating on using plant-based amendments will preclude most nutrient problems as they're nutrient profiles are balanced in the correct forms and more easily assimilated. What happens too often with new gardeners (regardless of what they're growing) is that they find a 'solution' and then begin looking for the 'problem' to fix when more often than not there is not a problem. Look at your plants - they'll tell you everything necessary on what should be added or adjusted to maximize the plant's health and vigor. From my perspective striving for healthy plants is the first order of a process - yields and such will always follow as the genetics allow. That's my read anyway - YMMV LD
LD, thanks for the additional info. I can't wait til the day when all this "higher learning" I am getting really becomes second nature. With each bit of knowledge, the connection is becoming a little clearer. As far as healthy plants, that's what it's all about to me, too - Healthy, deep green color and good strong stems/branches. Nothing as beautiful as a healthy looking plant. JaK
JaK In alll seriousness - if you actually need calcium in your soil after the garden is moving forward, you don't have to go and buy liquid calcium which contains EDTA (Ethylenediaminetetraacetic acid) - pretty bad stuff. A friendlier method is to simply crush egg shells, cover 3x with organic apple cider vinegar and let it sit for a couple of weeks - you'll have calcium in a liquid form that won't wreck havoc on your health. If you roast the egg shells prior to soaking them in the vinegar you'll end up with calcium phosphate - again in a form that won't harm your or other living things. Just an idea................ LD
Jak, I did it, done it, and it worked! I'm not sure about the transformation that's caused by the burning or baking - it probably has something chemically related to the heating process - but what I did find as a great aid to the process was this. I took my egg shells and ran them through the food processor to get the smallest pariticle I could. I then placed this in a plastic baggie and using a rolling pin or a can of soup or a spray paint can (this), I just ground the heck out of 'em until they were as fine a powder you could possibly get at home. I don't think it makes a bit of difference in the end product quality but it sure does speed up the time to get there. There is no need to remove any membrane material and arguably to get the micronutrient value you shouldn't remove the membrane. It's contains a lot of trace nutrient value in addition to the Ca you're hoping to get. Definitely give this a whirl. A dozen eggs and a bottle of vinegar is a lot less expensive than grow-store nutes!
Possum/LD, great idea. I used to just crush up egg sheels and sprinkle around my plants. More than likely, by the time my plants had matured and fruited I hadn't gotten much benefit from the eggshells. MOst benefit probably would have been down the road, next spring when I planted again in the same soil. I imagine your application process is to dilute a tsp or so of the resulting "extract" with a gallon of water? Thanks for suggestion guys. The reason I am asking about this is because I am still considering using coco coir in the future and there seems to be considerable discussion on Calcium deficiencies. I guess this could be a good replacement for Cal/Mag which is often suggested in the coco coir threads. JaK
JaK Ventoux asked about the coir-calcium thing on another thread. At first I couldn't figure out where that statement might have come from and I finally figured it out - I think. Peat moss has a CeC of about 100 and coir pith has a CeC of about 70. Since one of the most active exchanges of mineral cations in the soil involves calcium then this is probably what has led to the comments/observations that coir is calcium light. Given the disparities between peat and coir, it's important that the humus source (thermal compost, earthworm castings, et al) are of the highest quality and with the addition of humic acid to increase the overall CeC of the potting soil mix, this will equalize whatever potting soil base variables that you go with, i.e. peat or coir. Both have advantages and disadvantages but with the proper humus component those differences are moot and shouldn't cause you any concern. HTH LD
LD, thanks for the knowledge. This stuff is actually starting to click for me. The CeC concepts were a bit of a challenge at first, but finally getting to the point where I don't have to think things through so much each time. It's cool stuff to me. Becoming an "organic grow nerd" is cool! JaK
In regards to making homemade calcium and calcium phosphate, would lemon juice work as well as apple cider vinegar? And what kind of application for the calcium phosphate?
Yes - by volume, i.e 1 cup of burnt, crushed shells and cover with 3 cups of organic apple cider vinegar. Or you could use the EM-1 fermentation method. You could also use limestone, calcite lime or oyster shell powder as they're Calcium Carbonate as well. HTH LD
LD Are liquid Magnesium additives produced without using EDTA? I'm just looking at the Cal-Mag Plus label and seeing Calcium Nitrate, Magnesium Nitrate, Iron EDTA. I'm guessing that the EDTA in the iron is what you were referring to...or is this label essentially saying all those things are processed using EDTA? I'm only asking all of this because my local shop sells "Just Magnesium" and I was wondering if that could safely fill the gap of the eggshell/vinegar mix and the iron already in my TM-7.