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Rock phosphorus, or dolomitic lime?

This 2014 growing season I had some calcium deficiency soil issues that I successfully treated with calmag.  In 2015, I want to be prepared for this so I don't have to resort to hand watering all my plants with calmag.  Should I amend my soil with rock phosphorus, or dolomitic lime?  Why?
 
Maybe.. Your soil Might have enough if the PH is wrong it will Lock it out of your plants,  if your soil doesn't have enough and PH is good adding ether one will help.  Adding to much could mess up your PH, so don't think More is better but I would add a little.   
 
I've also heard adding things high in calcium like eggshells would help but I assume that's not something you want to do if you have a big garden. I don't have experience with rock phosphorous or dolomitic like so I can't attest to that.
 
if you want to stay organic, and you are working with plain soil, what you want to add is muriate of potash, for phosphate and 'bone meal' or something similar for calcium.

if all else fails, i always suggest calcium nitrate. it is not however organic.

you will find that all the typical pelleted fertilzers like the tomato stuff you buy at home depot is basically potash and calcium sulfate with a little ammonia etc mixed with bentonite and dried into these little round clay balls. you might just try one of those fertilizers, though they can get expensive.

if you dont care about organic labels, then its really simple... calcium nitrate(cheap) or calcium ammonium nitrate(cheaper), for magnesium, epsom salt, for phosphate, muriate of potash is the cheapest, tho inferior to mono and di potassium phosphate with respect to purity and availability.

keep in mind you DO NOT need alot of phosphate compared to nitrate and potassium. like a ratio of 3 1 3 or 3 1 4, or maby even 2 1 3 for older plants.

the egg shell jazz is great if you eat like 12 dozen eggs a month, but most just dont. i dont get why people always reccomend it. i can see for a compost pile, egg shells would be great.
i eat like maby a dozen eggs a month, it would take saving a years worth of eggs just to add enough calcium for like one plant.
 
queequeg152 said:
the egg shell jazz is great if you eat like 12 dozen eggs a month, but most just dont. i dont get why people always reccomend it. i can see for a compost pile, egg shells would be great.
i eat like maby a dozen eggs a month, it would take saving a years worth of eggs just to add enough calcium for like one plant.
 
People recommend it because it's free if you eat eggs, is good in that it breaks down slowly so things like excessive rain won't waste it away if growing in pots, nor do you risk overdose without having to add more later in the season, nor raise pH as quickly, and if you eat a dozen a month for a year, you will have far more than needed for one plant unless you're actively trying to change pH through a calcium soil amendment (which could cause excessive calcium uptake).
 
Let's talk more about egg shell to mature pepper ratio.  I get about 50 hot peppers per egg shell out of potted plants (meaning the larger the plant and larger the pot, the more egg shells go into the pot soil).  It's up to you how many plants you can or can't support with egg shell based calcium.   It's certainly not a good plan for someone growing  several dozen plants in higly calcium deficient soil, but has proven to work well for those who recommend it.
 
an egg shell is calcium carbonate right?

so it will lower the ph of soil. its not going to do it drastically, but to be clear calcium carbonate is a base, although a weak one.

50 peppers from one egg shell? how do you calculate that? i dont believe it tbh, calcium carbonate is an awful source of calcium, and takes lots and lots in acidic conditions, if its the sole calcium source.

my guess is that your soil is providing the massive bulk of your available calcium.
edit:

https://customhydronutrients.com/zencart/calphos-50-pound-bag-p-370.html?cPath=75_79_226&zenid=f0maabg35gue8fesj542jvg4c7
 
queequeg152 said:
an egg shell is calcium carbonate right?

so it will lower the ph of soil. its not going to do it drastically, but to be clear calcium carbonate is a base, although a weak one.

50 peppers from one egg shell? how do you calculate that? i dont believe it tbh, calcium carbonate is an awful source of calcium, and takes lots and lots in acidic conditions, if its the sole calcium source.

my guess is that your soil is providing the massive bulk of your available calcium.
edit:

https://customhydronutrients.com/zencart/calphos-50-pound-bag-p-370.html?cPath=75_79_226&zenid=f0maabg35gue8fesj542jvg4c7
 
I calculate it baed on putting 20 egg shells in a 20 gallon pot that has a pepper with 1000 pods on it, and so on.  So, about 1 shell per gallon, possibly 2 if I have extra shells.  I mix it all up before putting it back in pots so some may get a little more than others but that's the average..
 
No point in guessing, I reuse the same soil every year and egg shells are my exclusive source of calcium.  The soil was otherwise depleted years ago except for minor traces in amendments that don't have much calcium in them.
 
calcium carbonate is a GREAT source of calcium.  The point is that it breaks down slowly.  The worst thing possible is to add something that breaks down quickly then you have calcium overdose or else you have to keep adding calcium throughout the season to avoid a deficiency.
 
You are overthinking things.  I "do this", have for many years, and it works great.  Granted, I have peat, pine needles, leaves, etc based compost and slightly acidic rain (doesn't everyone these days??) to keep soil slightly acidic.
 
PS - Calcium carbonate does not lower soil pH.  Lower soil pH is more acidic and calcium carbonate will make an (already) acidic soil drift slowly towards neutral pH.
 
20 egg shells sounds about right. thats what 40-60 grams of calcium carbonate?

composted organic material is rich with nutrients including calcium.

are you adding new fresh compost to your soil every year?
edit

nah an egg shell is what maby a gram? so 20 grams of calcium carbonate?
 
I'd get the soil tested before doing anything. All states have an extension service in connection with an agricultural college, and they all do soil testing. Why guess what the soil needs? Besides, it pays for itself in that the results tell you what the soil needs and what it doesn't so you don't waste time and money adding things the soil doesn't need. Tell 'em what you're growing and they can help you fine-tune the nute levels for that crop.
 
http://extension.oregonstate.edu/find-us
 
ever had it done? i dont do anything withsoil so i personally have not.

id be curious to hear anyones first hand. my understanding was that it costs like 75 bucks for a soil test, more for a leaf tissue test.
 

John1234

Inactive Members
Hello Elephant in the room...
 
 
Correct me if I'm wrong, but don't both these sources provide almost zero nutrients in the first 12 monthes? Comparatively speaking, I believe they're both release around 1-5% of potential nutrients in the first year.
 
Bone meal, agricultural lime, oystershell flour or gypsum all appear to be better choices.
 
I too use the egg shell method, but I add mine to my compost pile so that they get crushed up and mixed evenly in the soil and have some time to break down a bit.
 
When I lived in Taiwan eggshells in pots were an extremely common practice, that is where I learned to do it. I raise chickens, so naturally I have quite a lot of egg shells.
 
The reason why people suggest this frequently is because it is a readily available resource - not because it is a perfect solution.
 
I use bone meal and agricultural lime as well when potting peppers up in to larger pots.
 
I never been able to completely get away from a liquid Calcium/Magnesium supplement though, provides a quick fix for low quality peppers that other supplements can't provide in the required time frame.
 
miguelovic said:
Hello Elephant in the room...
 
 
Correct me if I'm wrong, but don't both these sources provide almost zero nutrients in the first 12 monthes? Comparatively speaking, I believe they're both release around 1-5% of potential nutrients in the first year.
 
Bone meal, agricultural lime, oystershell flour or gypsum all appear to be better choices.
 
I've been looking around the internet a bit, but come up empty for evidence supporting your "Elephant".  I'd like to see it if you can dig something up.
 
I happen to have a bag of Down to Earth pelletized Rock Phosphate, and a bag of Lilly Miller Soil Sweet Lime on hand, which is why I am asking about these two amendments, in particular.  I noticed that the lime can be used as a side dressing for established plants.
 
Crushed oyster shells and agricultural lime are my go-to solutions. I buy a cubic yard of "gardeners mix" soil from a local source every other year or so and as soon as I get it home I mix in about 5 lbs of crushed oyster shells. When I'm ready to pot plants I start with about 5 cu. ft. of that mix in a wheelbarrow, mix in about a cu. ft. of good quality mulch and top it off with about 2 cups worth of the lime and 1 cup of all purpose timed released fertilizer. After a good mixing I pot up all my plants and give a loose handful of DE as a top dressing.
The oyster shell are very slow to release calcium and the lime is nearly instantaneous but washes out easily after a few waterings. A tablespoon of lime as top dressing followed by watering in done once a month seems to keep away blossom end rot on my peppers and tomatoes.
 
Sorry, went a little off topic but oyster shells and ag lime are what I know works for me.
 
miguelovic said:
Hello Elephant in the room...
 
 
Correct me if I'm wrong, but don't both these sources provide almost zero nutrients in the first 12 monthes? Comparatively speaking, I believe they're both release around 1-5% of potential nutrients in the first year.
 
Bone meal, agricultural lime, oystershell flour or gypsum all appear to be better choices.
agricultural lime, last i checked was calcium carbonate, so is 'gardeners lime'. its basically mined lime stone crushed to dust.
its called 'agricultural', because it wont rape the soil ph. or at least thats what i understand.

oyster shell is probably mostly calcium carbonate too.

dolomite lime is another mined mineral its supposed to be calcium magnesium carbonate.

quick lime, the stuff you make cement with is calcium oxide. very caustic, and very hydroscopic. its made by burning lime ( calcium carbonate) at like 1500 degrees untill all the co2 is driven out.

hydrated lime is calcium hydroxide. pretty caustic. its, as its name suggests hydrated calcium oxide.
if you heat the Jesus out of calcium hydroxide you will get calcium oxide once again.

the more you know.

regarding how fast its available...i imagine it would depend on how small the particles are, how acidic the soil is, and how wet the soil is. probably depends on number of other things too.

gypsum should be more soluble, but its still not great.

bone meal is probably a good way to get nutrients... i think its just incinerated organic material right? probably the same thing as potash.

if its been burnt up, its probably a bunch of oxides of phosphate and potassium and calcium.
IDK about nitrogen tho. ammonia and nitrate will oxidize to n2 and no when they have the bejesus heated out of them.
Hawaiianero said:
DE as a top dressing.
whats the DE for?
 
queequeg152 said:
whats the DE for?
Other than to make life miserable for any hard shelled critters that happen to come along, it's got trace elements of silica and iron oxide which at the very least doesn't cause any harm and I like to think can actually help the plants.
 

John1234

Inactive Members
queequeg.jpg

 
Made that for ya. Took me awhile to learn how to stitch.
 
 
Roguejim said:
 
I've been looking around the internet a bit, but come up empty for evidence supporting your "Elephant".  I'd like to see it if you can dig something up.
 
I happen to have a bag of Down to Earth pelletized Rock Phosphate, and a bag of Lilly Miller Soil Sweet Lime on hand, which is why I am asking about these two amendments, in particular.  I noticed that the lime can be used as a side dressing for established plants.
 
Damnit, I was looking for that reference before I posted, but figured it would be queequeg questioning the validity of that. Blundered around for awhile before I just said fark it.
 
Here we go, after more searching
 
Organic Soil Amendments for Sustainable Agriculture: Organic Sources of Nitrogen, Phosphorus, and Potassium
 
P in rock phosphate and bone meal has the formula Ca5(OH)(PO4)3, which is hydroxy apatite (or apatite, for short), the same material that bones and teeth are made of. Our teeth are evidence that apatite is quite durable and very hard to dissolve in water, meaning that it provides very little phosphate to your crop in the short term.
 
For further reading, poke around on the breakdown of rock phosphate under akaline (recently limed soil, perhaps) soil conditions.
 
Damnit, having trouble finding the exact source of annual availability. Not exactly what I was looking for, but shows minor availability of nutrients in rock phosphate. Hence treating with acid to produce MAP, DAP, etc, to create soluble conventional P amendments. If you're reusing potting soil or in the ground/beds, it's obviously got it's benefits over long period of time.
 
As for dolomite, one and two should work as primers on that. If you've got it, use it I suppose. Most potting soil (which I believe you're growing in) is limed with dolomite, and I would be hesitant to throw more Mg at it to provide Ca. Similar to the potential problem of heavy use of Cali-magic and other "Cal-Mg" bottled products to provide calcium. I don't put a huge amount of faith in the various nutrient ratio paradigms around, but it's common understanding across the board that excess of any nutrient will cause uptake issue.
 
miguelovic said:
Damnit, I was looking for that reference before I posted, but figured it would be queequeg questioning the validity of that. Blundered around for awhile before I just said fark it.
 
Here we go, after more searching
 
Organic Soil Amendments for Sustainable Agriculture: Organic Sources of Nitrogen, Phosphorus, and Potassium
 
P in rock phosphate and bone meal has the formula Ca5(OH)(PO4)3, which is hydroxy apatite (or apatite, for short), the same material that bones and teeth are made of. Our teeth are evidence that apatite is quite durable and very hard to dissolve in water, meaning that it provides very little phosphate to your crop in the short term.
 
For further reading, poke around on the breakdown of rock phosphate under akaline (recently limed soil, perhaps) soil conditions.
 
Damnit, having trouble finding the exact source of annual availability. Not exactly what I was looking for, but shows the slow breakdown of rock phosphate. Rock phosphate referenced anywhere is refered to as a slow release nutrient. Hence treating with acid to produce MAP, DAP, etc, to create soluble conventional P amendments. If you're reusing potting soil or in the ground/beds, it's obviously got it's benefits.
 
As for dolomite, one and two should work as primers on that. If you've got it, use it I suppose. Most potting soil (which I believe you're growing in) is limed with dolomite, and I would be hesitant to throw more at it to provide Ca. Similar to the potential problem of using Cali-magic and other "Cal-Mg" bottled products to provide calcium. I don't put a huge amount of faith in the various nutrient ratio paradigms around, but it's common understanding across the board that excess of any nutrient will cause uptake issue.
Thanks for getting back. I'm using raised beds. I'm not sure which way to go now since I already amended the beds with alfalfa meal and composted chicken manure, and 4" mulch. My intention is to reamend the beds 1-2 months prior to plantout. I'll deal with the calcium issue then, I guess.
 

John1234

Inactive Members
Hmm, didn't really intend to discourage you, just to explain my reasoning. For the record, I use rock phosphate and rock dusts, etc, for long term nutrients, and have used Ca-Mg in a pinch, waiting for nutrients to break down. With fresh OM and mulch, and the usual mild PNW winter, I would imagine the worm will go nuts, and there will be abundance of Ca available next year, otherwise it may be another issue.
 
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