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Chelates for trace minerals?

Dreambig

Member
How do you guys feel about adding chelated copper, manganese, and fertibor to an organic soil? Will these chelates have a negative affect on the microbes? And could someone help with the formula used to amend a 250 gl. Pot. My manganese level is at 9 ppm. The chelate I'm thinking about using is 13% manganese. The guy at the store said 7.5 ozs would raise my 250 gl. 30 ppm but I'm not quite sure how he came up with this number. I would really like to figure out how to calculate these formulas. My copper level is at 0.44 ppm and the chelate is 14%copper. My boron levels are at 0.63 and fertibor is 15.2%... Or do you guys think I should just scratch the chelates and use something like sea crop or micropak as a foliar? Also I have some lama and dairy manure around, do you think either of those would provide enough micronutrients?
 

juan93

New member
their are better sources for trace minerals then chelated nutrients, especially for organic soil, look into comfrey, alfalfa, or kelp meal, etc. but here is an article that you might find helpful.

CONVERSATIONS ON CHELATION AND MINERAL

NUTRITION
Much has recently been said about mineral absorption into plants, and there are recent
pontifications that the best way to supplement minerals is to take "Colloidal" mineral
complexes, while still others professing that "Sulphates" are the way to go, and that
"Chelated" minerals are supreme due to their bioavailability.
Everything you hear has some ring of truth to it; each side has a point to make. But
unfortunately, neither side has ever told you the whole story about mineral uptake and
balance in plant nutrition, and the limits of all the above methods of mineral
supplementation. This has led to considerable confusion, misinformation and to the drawing
of many inaccurate conclusions. Can it be simplified? Perhaps gaining a better understanding
of what each category is may help reduce the confusion allowing growers to make a better
decision about what to use.

INORGANIC SALTS
These are simple mineral compounds such as sulphates or chlorides. Plants are accustomed
to dealing with minerals in this form, but don’t always do a good job of controlling
absorption. Although mineral absorption increases when there is a mineral shortage, and
decreases when mineral levels are high, the plants mineral transport system often misregulates
minerals that share the same transport channels. For example, when copper and
zinc salts are consumed together, they compete with each other for transport into the plant.
An excess of zinc can therefore cause a deficiency of copper. If one’s purpose in using
mineral fertilizers is to force the plant to use more minerals than it normally would, the
inorganic salts would be a poor choice. The rates of application for inorganic salts can be
quite high and the frequency of application is also frequent, therefore making the total cost
of inputs quite high over the growing season.

OXIDES
An oxide is a raw version of a mineral. For example, Iron Oxide is also known as “rust”.
How soluble is rust? Magnesium oxide is insoluble; however it is used in commercial
formulations as a source of magnesium. Oxides can only be dissolved using acids. The
availability of oxides is extremely low and these types of formulations are better used in soil
applications not as foliar sprays. Companies selling these formulations state that the product
is ground to a fine powder rendering it soluble or available. The texture of the product has
never been a criteria for the availability of any product. Only the formulation of the
product specifies its solubility and availability.

COLLOIDS (SUSPENSION FERTILIZERS)
Colloids are materials made up of solid particles of such small size that when dispersed in
water they remain in suspension rather than sinking. Colloidal minerals consist of mineral
salts or other mineral compounds converted into colloidal form, either by grinding or by
rapid crystallization.
Most colloidal substances are poorly bio-available, since the colloidal particles, small as they
are, are nevertheless far too large to be absorbed whole, and nearly all of the active
ingredients are trapped in the interior of the particles, where they cannot come into contact
with the transport channels in the cells. However, if a colloidal substance can dissolve, it
would then release all of its mineral material for potential absorption.

EDTA
EDTA or ethylenediaminetetraacetic acid is a novel molecule used for
complexing minerals. EDTA is a synthetic chelating agent which binds
to an element and is used in cosmetics, medicine and plant nutrition. It
is an agent which can not be utilised by the plant (never breaks down)
and binds to minerals such as Calcium very tightly and makes the
mineral less available once inside the plant. The complexed molecule is
large and enters mainly from the underside of leaf. Too much EDTA is
toxic to plants. EDTA is best used in pH’s below 7.

MIXTURES
Research has shown that chelated minerals are very important to plant nutrition; hence many
companies have rushed to the marketplace with their own brands of “chelated minerals”
without doing any research to determine whether or not their methods of chelation will
actually enhance the absorption of the mineral. The only objective of these companies is to
produce a “new” type of mineral fertilizer whereby their only objective is to gain profit from
calling their product a chelate.
Many products claim to be amino acid chelates, however when formulations are reviewed, it
is apparent that they are mixtures not chelates. The terms “chelate” and “amino acids” are
used very loosely. These products, of which there are many in the New Zealand marketplace,
are formulated by using protein powder and mineral salts, mixed together and the resulting
product is a mixture, but wrongly called a chelate. Mixtures tend not to carry patent numbers
as there generally is nothing to protect about the formulation. Mixtures are very expensive
for an imitation of a chelate.

ABOUT CHELATES
The word “chelator” refers to a substance consisting of molecules that bind tightly to metal
atoms, thus forcing the metal atoms to go wherever the chelator goes. The bound pair —
chelator plus metal atom — is called a “chelate”. Chelators of nutritional interest include
amino acids, organic acids, proteins, and occasionally more complicated chemicals found in
plants.

AMINO ACID CHELATES
Amino acids can act as chelators when they react with positively charged metal atoms,
forming a strong chemical bond. The metal atoms of interest here are those that serve as
minerals. To take a specific example, a chelate can be formed between the amino acid glycine
(the chelator) and calcium (the mineral).
Certain combinations of minerals and amino acids do not form good chelates because the
chemical bonding is too weak. For example, if you try to use the amino acid glutamic acid as
chelator and sodium as the mineral, you can get monosodium glutamate, which is considered
to be merely an “organic salt”, not a chelate. Generally speaking, sodium and potassium
form poor chelates.
Furthermore, amino-acid chelation bypasses the competitive interactions that can occur
between different minerals when they are absorbed as salts. Use of chelated minerals avoids
this problem since they are transported by different mechanisms.

THE AUTHENTIC CHELATES
The National Nutritional Food Association (NNFA) created a definition of what an Amino
Acid Chelate is in 1996;
Metal Amino Acid Chelate is the product resulting from the reaction of a metal ion from a soluble metal salt
with amino acids with a mole ratio of one mole of metal to one to three (preferably two) moles of amino acids
to form coordinate covalent bonds. The average molecular weight of the hydrolyzed amino acids must be about
150 AMU (Atomic Mass Units) and the resulting chelate must not exceed 800 AMU. The minimum
elemental metal content must be declared. It will be declared as a METAL amino acid chelate: e.g. Copper
amino acid chelate.
-Adapted by the NNFA Board of Directors, July 1996
For a true functional chelate, the following further requirements must be met:
1) The chelate must have a molecular weight less than 1000 daltons.
2) The chelate must be electrically neutral. The chelate must not be complexed with an easily
ionisable anion, such as a halogen or a sulfate group; the ligand must satisfy both the
oxidative state and a coordination number of the metal atom.
3) The chelate must have a high enough stability constant to avoid competitive chemical
interactions prior to absorption.
4) The ligand must be easily metabolised.




Chelated nutrients are more plant available than complexed nutrients (EDTA, EDDHA,
etc), and complexed nutrients are more plant available than mixtures and uncomplexed
nutrients (Quelant, Sulphates and Oxides) as can be seen in the table above.

COMMERCIAL AUTHENTIC CHELATES
An authentic chelate has all the properties specified above by the National Nutritional Food
Association (NNFA). There are two companies worldwide that actually carry patents for
manufacturing “authentic chelates” of which Glycine
technology is involved in both patented processes. What is
Glycine technology? It is a patented process of chelation
whereby every element is bonded with two Glycine (smallest
amino acid) molecules creating a fully chelated product. The
plant recognises this molecule as a protein like nitrogen,
allowing it to travel in the phloem quite readily to the
growing points such as flowers, fruit and berries where is it
required, as well as replenishing leaf levels also. This allows
the element to be a mobile element in the Glycine chelated
form whereas metals normally have low mobility within the plant. This is especially
important for elements like Calcium and Boron.
The Glycine technology methods of delivery are not conventional, like the delivery methods
of products such as oxides, sulphates and EDTA based trace elements. The latter products
can marginally reduce a deficiency, but the speed by which the elements are released from
these products and transported into the growing points is very slow compared to the
transportation of elements in the Glycine form.
How does one evaluate chelates against the other mineral forms in the marketplace
which also talk of availability?

Simply ask the following questions:
1) Does the product have a patent number?
2) What is the chelating agent in the product and what concentration is the chelate?
3) Are the minerals truly chelated to amino acids or just complexed or are they simply trace
minerals mixed with protein?
4) Is there proof of the chelate bond formation in the product?
5) Is the product stable when subjected to various pH ranges? (pH 4.0 - 7.5)?
6) Is the mineral product small enough in size to allow unhindered movement through the
plant?
7) Compare pricing. You may pay less for some reported chelates and complexes, but are
they really cheaper? If the product is not truly a chelate then you are essentially buying
inorganic minerals at a premium price. Without guaranteed availability, you lose two ways:
cost and mineral utilisation.

Only true amino acid chelates will give you your money's worth. Don't be fooled by
imitations.

Written by Asma Johansson (Horticulturist / Viticulturist) B.Sc. Agr (Hons)
Majoring in Viticulture and Plant Nutrition.
 

m_astera

Member
Veteran
Chelates are not necessary

Chelates are not necessary

Chelated minerals are not necessary and give no real advantage in biologically active soils. In addition, chelated minerals are extremely expensive, and EDTA chelates are potentially toxic and not allowed under USDA NOP organic standards. In most cases the important metals Iron, Manganese, Copper, and Zinc should be added to the soil in sulfate form. Boron is best supplied as Sodium borate (borax, Fertibor, Solubor)

What is most important is the ratio of the mineral elements to each other, and that there be sufficient minimum amounts. The rule for minimum amounts that I use is:

Boron B 1ppm
Iron Fe 50ppm
Manganese Mn 25ppm
Copper Cu 5 ppm
Zinc Zn 10 ppm
(above as measured by a Mehlich 3 soil test)

Note that ppm, parts per million, is a measure of weight of oven-dry soil. Dreambig is talking about a 250 gallon pot. Take one gallon of the soil packed as it is in the pot, oven dry at ~250*F, and then weigh the gallon of soil. Let's say a gallon weighs 4.4 lbs. or 2 kg. 250 gallons would be 250 x 4.4 = 1100 lbs. or 1000 kg. (It's much simpler to use kg and grams to calculate small amounts like this)

One part per million is 1 milligram per kilogram. 1ppm of 1000 kg would be 1000 milligrams or 1 gram. If we wanted to add the above minimum amounts to 1000 kg of this soil we would want to add
Boron B: 1 gram
Iron Fe: 50 grams
Manganese Mn: 25 grams
Copper Cu: 5 grams
Zinc Zn: 10 grams

The actual amounts added will depend on the concentration of the element in the amendment. Commonly used USDA NOP Organic allowed mineral amendments are

Sodium borate (20 Mule Team Borax: 10%B
Ferrous sulfate heptahydrate 20%Fe
Manganese sulfate 32%Mn
Copper sulfate 25%Cu
Zinc sulfate 35%Zn

To calculate the total amount to add, the amount desired is divided by the percentage concentration of the desired mineral, e.g.

1 gram B / 0.10 = 10 grams borax 10%B
50 g Fe / 0.20 = 250 g FeSO4 20%Fe
25 g Mn / 0.32 = 78 g MnSO4 32%Mn
5 g Cu / 0.25 = 20 g CuSO4 25%Cu
10 g Zn / 0.35 = 27 g ZnSO4 35%Zn

These would be the minimum amounts for a soil with a cation exchange capacity (CEC) of 7 meq or less. A soil with a CEC of 14 would need 2x these amounts, minimum, a soil with a CEC of 28 would need 4x these amounts etc.

Most soils will already have some amount of these elements present, so obviously one would only want add the amount needed to bring the minerals into balance.
 

Granger2

Active member
Veteran
Good article posted by Juan. I would discourage you from mixing your own trace mixes. Sea Crop is a really great product. I use it as a drench, and foliar. I use primarily 2 trace products. Earth Juice Microblast and SaferGro Biomin Starter. I only use the SaferGro occassionally during a crop if at all. Note that it contains 2% N. EJ Microblast has no N. That's what I use most of the time.

My recomendation is to use Sea Crop regularly as a drench, and Microblast if and when the plants need more greening than the Sea Crop provides.

Mixing your own is tricky, and I don't think the savings are worth the risk of miscalculation and resulting damage to plants. Microblast has been on the market for many years, is reasonably priced, and is a big seller. Good luck. -granger
 

m_astera

Member
Veteran
Granger 2-

Allow me to explain why your suggested mineral sources are less than optimal.

First of all, we are talking about the secondary elements, not micro-trace elements that are only needed at an ounce or two per acre. Plants need and use a lot of Iron, Manganese, Copper, Zinc and Boron. The "minimum" amounts listed in my first post have been proven to work by hundreds of real world growers over the last dozen years. Let's take Copper and Zinc for examples. Copper is known to be a cofactor in the synthesis of many enzymes and is essential to the immune system of both plants and animals. In plants Cu is a major component of their ability to resist fungal diseases. Zinc is known to be essential for the synthesis of at least 300 enzymes.

I'm looking at a lab soil test for a raised bed garden in Trinity County, CA, from April 2014. The soil's CEC is 16.37meq. In order for the minerals to be balanced, this soil should have 12.75ppm Cu and 25.5ppm Zn. The lab test shows 2.9ppm Cu and 32.4ppm Zn. Not only is Copper deficient, but Zinc is excessive, which will make the Cu deficiency worse. Any crop grown in this soil will be Cu deficient and have a weak immune system. In order to balance things, we need to add at least 12.75 - 2.9 = 9.85ppm Copper. Call it 10ppm Cu.

How much of the mineral sources you suggested would be needed to add 10ppm Cu? Here is the analysis for Safer-Gro Biomin Starter:
Total Nitrogen (N)……………2.0%
Magnesium (Mg)……………..0.8%
Boron (B)…………………………0.025%
Copper (Cu)…………………….0.1%
Iron (Fe)………………………….0.5%
Manganese (Mn)……………..2.5%
Zinc (Zn)……………………………..1.5%

0.1% Copper. Which is 0.001 (one thousandth) of the total. My earlier post suggested a dry weight of 1000kg for a 250 gallon pot. Using that same estimate for this soil that needs 10 ppm Cu, we would want to add 10 grams of elemental Cu per 250 gallons. How much Biomin Starter would that take?

10 grams / 0.001 = 10 000 grams or 10 kilos of Biomin Starter would be needed, per 250 gallons, to add a measly 10 ppm Copper. But let's recall that Biomin Starter contains 1.5% Zinc; that 100 kilos of Biomin would also be adding 150 grams of Zn, 15 times as much Zn as Cu, when Zinc is already too high.

How about the Earth Juice Microblast? Here is its official analysis:

Magnesium 0.50%; Boron 0.02%; Cobalt 0.0005%; Iron 0.10%; Manganese 0.05%; Molybdenum 0.0005%; and Zinc 0.05%

It wouldn't be possible to correct a Cu deficiency with EJ Microblast because it contains zero Copper, none.

Sea-Crop was the other "trace" element source mentioned. Although I have great respect for Sea-Crop, Sea 90, kelp, and seaweed extracts they are only dependable as sources of micro-traces, elements that are needed in vanishingly small amounts. Kelp on average contains around 0.06% Cu. Sea salt contains around 0.002% Cu, or 0.00002 of the total mineral content.

Relying on sources like these for important minerals that are needed in significant amounts in healthy soils and plants doesn't work. On the other hand, a $20 soil test combined with a little knowledge and basic arithmetic shows that you can have the precise amount of Copper needed in that 250 gallon pot by adding 40 grams of Copper sulfate 25%Cu, at a cost of fifty cents or less, and not have to wonder how many other elements were added that were not needed.
 

Dreambig

Member
Thanks guys, the route I chose was I added a little bit of fertibor to cover the boron and I've also been adding tm-7 to my compost teas right at the very end before I feed the aact. Also foliared with tm-7 and sea crop a couple times. Plants have been doing great so far and I'll be I sent in another soil analysis last week so. Should have the results by the end of the week. I've also been using those two products on my indoor and I'm seeing big difference in veg and bloom. It's amazing how micronutruients make such a big difference and I doubt I'm at the levels I need to be. Here's the tm-7 label. It's mostly sulfates
 

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m_astera

Member
Veteran
Dreambig- Good to hear you are getting the soil tested. My main argument against relying on mineral potions and foliars for minerals is that the soil can remain unbalanced and nutrient deficient An analogy would be a child who is being fed a diet lacking in nutrients but given an occasional IV injection of nutrients in some haphazard mixture without knowing if they were really needed or not. It's wiser to provide a complete and balanced diet in the first place.
 

Granger2

Active member
Veteran
Astera,
You're talking about changing the soil long term in one application. I'm talking about multiple supplemental feedings of the plants to compensate for inadequacies of the soil. That's what Dreambig was asking about. He says his plants are doing very well now with what he has applied.

If he wants to reuse the same soil, or if he wants to mix more he will have the insite from his soil tests, info provided by you and others, and his personal experience to apply things that will make lasting changes to his soil so liquid supplements may not be needed.

You were addressing long term, I was addressing short term corrective action. Good luck. -granger
 

cyat

Active member
Veteran
nice info

i noticed canna doesnt use chelates, and they have the cleanest ferts
 

milkyjoe

Senior Member
Veteran
Michael...are you opposed to foliar completely? If no can a mineral or ion for that matter make it into the plant without chelation?

And ignoring organic certification do oxides make good sources for soil amendment micros?

Thank you for adding to the forum. Your input is greatly appreciated
 

m_astera

Member
Veteran
milkyjoe-

I'm not opposed to foliars at all. Spraying beneficial microbes, humates, seaweed, compost teas and so on works great.

But I don't think foliar sprays are the best way to apply or amend minerals. Ditto for applying them through a drip line in a just-in-time fashion. My view is that plants should get their food from the soil just like people should get their nutrition from their food and not have to take supplements. If the food provides complete nutrition there should be no need for vitamin or mineral supplements.

lf the soil is lacking in essential minerals to the extent that the plants need to be supplemented I think there is already a problem and one is applying rescue chemistry to save a less than optimally healthy plant. Growers don't adopt that attitude toward NPK; on the contrary N, P, and K are usually kept at luxury levels so the plants can take up all they want. I take the same view toward minerals like S, Fe, Mn, Cu, and B. The soil and plants don't need as much of those elements as they do NPK but they are no less important to the health and growth of the plants.

Another way of looking at it: When quality dog food or chicken feed is formulated every effort is made to provide complete nutrition in the end product. We don't expect to have to feed supplements too. One reason commercial chicken manure is such good fertilizer is because their feed has been fortified with the secondary minerals listed above. The chickens are fed iron, manganese, copper and zinc sulfates along with plenty of boron and lots of calcium and magnesium. High levels of all of the above show up routinely in lab tests of soils fertilized with large amounts of commercial chicken manure.

I advocate the same approach to soil as to formulating a complete animal "chow": If possible, provide every element the plant needs at luxury levels throughout the growing season, right from the start, in the growing medium.
 

m_astera

Member
Veteran
Metal oxides as soil amendments

Metal oxides as soil amendments

Metal oxides are generally much less available than sulfates. Few of them are water soluble at all. Where they work and work well is in soils with naturally high levels of sufates, e.g. gypsum based soils, or soils that have been over-amended with sulfates. In that case the abundant SO4 will solubilize the oxides and make them available.

One exception to this rule is magnesium oxide, which solubilizes easily and works faster as an Mg amendment than dolomite lime while having little or no effect on soil pH. MgO is also often a better choice than Epsom salts, because it is ~50% Mg, whereas Epsom salts is only 10% Mg by weight, and 14% S.
 

guineapig

Active member
Veteran
The greek root of the word "Chelate" is "Crab Claw," and the chemical chelate does sort of
pinch the nutrient molecule like a claw.

I remember reading about a South African chemist who developed very exotic chelates for
all nutrients, even micro-nutrients, and he named it "The Shuttle System" for the way the
nutrients were transported into the plant. But these chelating agents were quite rare and
I assume expensive as well.

I will try to research it more, it's been awhile since I read up on Chelation molecules.

:ying: kind regards from guineapig :ying:
 

unklemike

Member
I try not to over think the amount of macro/micro nutrients or trace minerals. a well balanced compost pile or worm bin with rock dust added is primo. As for amendments kelp meal has trace minerals and enzymes that has amazing effects and is superior to bottled liquid seaweeds. I wouldn't chance bulk chemically chelated amendments and also it defeats the purpose of living organic soil.
 

m_astera

Member
Veteran
I try not to over think the amount of macro/micro nutrients or trace minerals. a well balanced compost pile or worm bin with rock dust added is primo. As for amendments kelp meal has trace minerals and enzymes that has amazing effects and is superior to bottled liquid seaweeds. I wouldn't chance bulk chemically chelated amendments and also it defeats the purpose of living organic soil.

Not "over thinking" the amount of macro/micro nutrients or trace minerals translates to me as "I don't want to learn anything". The ending appeal about defeating the purpose of living organic soil makes no sense. What exactly is the "purpose" of "living organic soil" that would be defeated by having all of the essential minerals, in balance, in optimal amounts, available to the crops and the soil organisms? Might they get too healthy?

Check out the minerals in a good soil test from the best agricultural soils in the world, those that grow the healthiest crops and the healthiest animals. Arguably, in the USA, these would be the soils either side of the 98th meridian that runs from the border between the Dakotas and Minnesota down to the Houston TX area. This is where the buffalo roamed in their millions and remains the area with the best grazing in the world, simply because of the mineral richness of the soil. Going East from that line, the soils become more leached out due to higher precipitation; going West, there are less minerals available because of scant precipitation and poorly developed soils. The soils in the northern parts of this fertility band developed from rocks brought in from a vast area by glaciers and left behind when they retreated. They were further enriched by dust blown in from the Rocky Mountains and plains and river valleys to the West. It has been estimated that around 1/4 inch of new mineral dust is deposited yearly on these soils; that is 25 inches (63cm) per century. This is where the best high-protein wheat has been grown for the past 150 years, the best cattle, the most nutritious food period. Until recently it also had the healthiest people with the fewest number of tooth caries. All due to the mineral content of the soil.

Do you know that Calcium is far and away the most important mineral in any soil, in quantity and in function? Any soil that produces truly healthy crops needs at least 1000 parts per million Ca; many soils with high CEC need five or seven times that much Ca. Do you think you can supply that with compost and kelp meal? Good luck. Kelp meal runs about 2% Ca. To add 1000ppm Ca to the top 6" (15cm) of an acre of land would call for 100,000 lbs of kelp, or 100,000 kg/ha. Adding 5 ppm Copper to an acre would call for 16,000 lbs of kelp.

Relying on compost or barnyard manure to provide sufficient or balanced minerals is no better. As for "rock dust" pray tell what is that? The powder from a rock crushing operation? What is the mineral content of the rock being crushed? Is there anything in that rock dust that your soil needs? How about rock dust that contains large amounts of minerals that your soil already contains in excessive amounts? Adding more of what you already have too much of will only throw a soil further out of balance and increase mineral deficiencies in the crops.

If you choose to practice "faith based" agriculture and remain uninformed about the huge body of knowledge about minerals and their relationship to soil, plant, and animal health that has been painstakingly gathered over the last two centuries, fine. But I wouldn't brag about it or encourage others to follow your example unless you can provide some convincing evidence that supports your claims. I don't think that can be done.
 
C

Cep

I have a question about last minute applications of trace mins via drip line: How inefficient is this method and how would one try and adjust the drip application amount if there is some already being delivered via weekly foliars?

During the spring amendments I added compost that had a significant amount of Boron so I did not add any other sources to my deficient soil. Final testing showed levels between .4-.8ppm even after the compost application. My cec is around 15 and I've got boric acid, but I'm applying foliars that contain Boron. I've been wondering these past few weeks if I should still apply the amount via drip that would mathematically bring me to 1ppm i the soil while still doing foliars.
 

m_astera

Member
Veteran
Cep-

Adding soluble minerals through the drip line is efficient for small quantities, it's just not efficient for balancing the primary elements, especially Ca.

A soil with a CEC of 15, pH 7 or less, with Ca at 70% saturation (2100ppm Ca), should have 2.1ppm boron in the soil. (Ideal boron at 1/1000th of calcium). So you could definitely and safely add more B if the soil has enough Ca.

Interestingly, on p124 of Wm Albrecht's "Soil Fertility and Animal Health" (AcresUSA 1975) photos are shown of a soybean plant growing in media amended with 0, 13, 26, and 52 ppm boron. All except the plant getting 0 appear fine. But I don't recommend more than 5ppm.
 

m_astera

Member
Veteran
"Adding soluble minerals through the drip line is efficient for small quantities, it's just not efficient for balancing the primary elements, especially Ca."

Think I need to qualify that statement. *If* the plant has a mineral deficiency during the growing season, adding the needed minerals via drip fertigation will help. The best method is to have all of the necessary minerals available in the soil so deficiencies don't happen in the first place.
 
C

Cep

Think I need to qualify that statement. *If* the plant has a mineral deficiency during the growing season, adding the needed minerals via drip fertigation will help. The best method is to have all of the necessary minerals available in the soil so deficiencies don't happen in the first place.

Right. What I'll prob do from now on is start testing/amending earlier in the season if possible. All I really need as far as traces is a little more boron and copper. I'm waiting on a petiole analysis before I proceed. Thanks for your reply.
 
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