Soil Testing Results in my garden in CA

[Redbaron]

Originally Posted by Ms. Jitomate

Well, I put more time researching this high level of zinc in my soil and I found this article from a Plant and Soil, June 1978, www.springerlink.com/index/3137N50553PV5585.pdf which states that it could stunt your corn. Corn was the last vegetable planted there this past summer and I did get the shortest corn stalks from previous years. I had no idea why. I thought it was weather related. It states,

"At 15.9 ppm Zn level, the growth of maize became stunted and this effect intensified with further increase in zinc level."

So I researched where this zinc may be coming from and I find another article from Clemson University, http://www.clemson.edu/public/regula...onutrients.pdf.
It states,

"In old peach orchards, zinc soil toxicity can occur following years of applying zinc-containing fungicides. Repeated use of sludge, slag, or poultry litter, all of which can contain high
concentrations of zinc, may result in soil zinc toxicity. The potential for a zinc toxicity can be
reduced or eliminated by liming the soil to raise the water pH above 6.0 or 6.5, the pH level
normally recommended for the crop growing or to be grown."

Well, I have been adding my chicken manure exactly 3 times in my three years I have had chickens. And, I have purchased chicken manure from the garden stores and added that to my soil prior to owning chickens. Could this be the real source of the increase in zinc? I thought chicken manure was one of the best organic fertilizers. Any thoughts?

Too much of a good thing can be bad. And most certainly while chicken manure is a good thing, it is very concentrated as manures go. So yes, this could be the reason, especially when you were buying it from factory farms.

Healthy soil contains 5-11% carbon in the A layer. You had 14% or so. That is OK in and of itself, but if that high carbon content was the result of mainly chicken manure instead of more mild herbivore manure like cow, horse, rabbit etc....Then sure that could be the root of the problem.

Just keep in mind, compared to most people your "problems" are minuscule! Your soil is awesome! Just give it a rest for a bit with the high powered additives! Give your soil biology some time to digest everything. And be sure to follow the instructions of the soil test. Don't forget the dolomite. That will help your soil biology deal with it all.

[dice]

Gypsum would not typically be high in zinc.

For example:
http://agr.wa.gov/PestFert/Fertilize...spx?pname=1925

Here is an organic fertilizer that actually is high in zinc:
http://agr.wa.gov/PestFert/Fertilize...spx?pname=3745

Here is a synthetic with comparably high zinc levels:
http://agr.wa.gov/PestFert/Fertilize...spx?pname=2614

Another:
http://agr.wa.gov/PestFert/Fertilize...spx?pname=2131

I have seen fertilizer products in that listing go over 10000ppm
zinc.

General overview of the problem of using toxic industrial waste
as fertilizer, with examples from a little more than two decades
ago:
http://www.cephas-library.com/health...ertilizer.html
(To what extent is this still happening? We don't know, but the
examples of fertilizers turning up with high zinc levels is not
reassuring.)

The zinc was probably in the rose food that someone used for years
before you bought the property.

[DavidP]

If everything is growing well i wouldn't worry too much. On a soil test i had done last year in probably not too dissimilar climate my zinc levels were 20ppm. That was in a garden area that is far from any housing structures and hadn't been actively gardened before. With a organic matter of 14% i'd guess you must have been putting large amounts of compost etc on there. my organic matter came in at 2.7. my soil type is sandy loam on decomposed granite bedrock.

[troad]

If you open this link http://agr.wa.gov/PestFert/Fertilize...spx?pname=1925 then look at the white box on the left there is a listing that says "Product Database" from here you can look up any fertilizer sold in Washington state. I am sure a lot of them are sold across the country. A few years back there was an expose on heavy metals in fertilizer sold here. Turns out the aluminum manufacturers were getting rid of their waste slag by selling it to companies that added the slag to their fertilizers. There are several fertilizers with very low Zinc content and low contents of heavy metals.

[ScottinAtlanta]

Folks, I am confused about the different kinds of lime referenced in this and other posts. What is the difference between using:

-- Agricultural lime (calcitic lime) - a post says "Ag lime is finely ground limestone(calcium carbonate)"
-- Dolomite lime - pelletized or powdered
-- Hydrate lime (calcium hydroxide)
-- Wood ashes used as a liming agent

Are some of these better for containers or for gardens?

[Doug9345]

Originally Posted by ScottinAtlanta

Folks, I am confused about the different kinds of lime referenced in this and other posts. What is the difference between using:

-- Agricultural lime (calcitic lime) - a post says "Ag lime is finely ground limestone(calcium carbonate)"
-- Dolomite lime - pelletized or powdered
-- Hydrate lime (calcium hydroxide)
-- Wood ashes used as a liming agent

Are some of these better for containers or for gardens?

Ag lime works over 3 to six months as the acid in the soil slowly dissolves the stone particles.

Dolomite lime is a mix of calcium carbonate and magnesium carbonate. I think the speed is similar and it adds magnesium to the soil.
To make hydrated lime, limestone is first heated until it becomes calcium oxide. The water is added to form calcium hydroxide. I'm going to guess that it's reaction with the acid in the soil is in the class of minutes or maybe hours instead of months. Given that it is caustic, think lye. Wood ash contains potassium hydroxide. Application rates I don't know. I've spread ashes lightly on my garden, but it tends to be acid anyway.

[dice]

The excess zinc could be in your water supply, too, rather
than a legacy that you inherited from a previous homeowner.

If you can gradually raise the soil pH up to about
7, that will reduce the uptake of zinc by plants.
You generally do not want to go much higher,
because the dropoff in phosphorous uptake above
pH 7.2 is steep, so you want to do it a little bit
each year and then test, rather than trying to go from
pH 6 to pH 7 all at once.

http://www.extension.org/pages/13064...h-modification

Here is a document on liming materials from Cornell that covers
everything but wood ash:
http://nmsp.cals.cornell.edu/publica...factsheet7.pdf

This document from Clemson has a chart at the bottom of the page
that relates wood ash to other liming materials:
http://hubcap.clemson.edu/~blpprt/acidity2_review.html

This document from U of Missouri has charts that relate ENM
(effective neutralizing material) to particle size and CEC:
http://extension.missouri.edu/public...b.aspx?P=G9107

[dice]

You can get Dolomite pretty reasonably at a big box store:
http://www.homedepot.com/p/Lilly-Mil...0#.UT-M99dlBxA

Here is the analysis on it:
http://agr.wa.gov/PestFert/Fertilize...spx?pname=4226

If you want to avoid raising the magnesium and use agricultural lime,
you can usually find similar quantities at other big box stores if HD
does not have it. You can also find it in 5lb bags from Espoma and
other companies.

The wood ash is actually a good idea. It will react with the soil
a lot faster than any kind of actual, mineral lime, and it has some
potassium, which would help the tomatoes. With high N and P,
you probably do not need to add anything else this year (aside
from the sulfur recommendation from the soil test lab). The
difficulty is in knowing how much wood ash to use for any given
square footage of garden. Without knowing that, one needs
to sprinkle some around, amend the soil, water it, and then test
the pH weekly or monthly to see where it stabilizes. If it gets over
7.0, you may need to add more sulfur to adjust it back downard
a little. (This may help: http://www.amazon.com/Luster-Leaf-18...words=ph+meter
Mine reads .1 low across the scale, so it is usable if one keeps that
in mind. I do not know if every one of that model is the same way.
I tested it with pH meter test solutions at pH 4 and pH 7 from a
hydroponics store.)

I would avoid bagged chicken manure for a few years. I do not know
if it is naturally high in zinc or if it is a side effect of adding zinc to
commercial chicken feed. I came across this while looking for zinc
levels in chicken manure from free-range chickens vs commercially
raised chickens: http://www.worldpoultry.net/Breeders...rds-WP001180W/
(It is possible that feed manufacturers are routinely boosting the zinc
in commercial chicken feed.)

The foundation and sidewalk are not a problem. What concrete in
contact with the soil typically does is add calcium that leaches out
of it slowly and raises the pH. At 6.0 and "medium" calcium, those
are not affecting your soil adversely.

[Ms. Jitomate]

Wow, Dice, you really found some good information! I will print this thread and keep it in my garden journal. I appreciate your help. I did call my city's water manager and asked about the zinc. He said it is not included in the reported water test analysis because it is not found in the water.

The Dolomite has been added and now I am working on the irrigation. Hopefully tomatoes will go in on March 17!

[dice]

(Actually the "Espoma Organic Garden Lime" looks like it actually
is Dolomite:
http://agr.wa.gov/PestFert/Fertilize...spx?pname=4866 )

Moot point now, but I did not want to leave anyone else reading
this thread with the wrong impression that it was simply lime
(meaning all calcium carbonate and no magnesium).