• Here is a link to the full explanation: https://rollitup.org/t/welcome-back-did-you-try-turning-it-off-and-on-again.1104810/

veg+bloom constant mag deficiency

im4satori

Well-Known Member
Asher and Edwards (1978a,b), in a series of interesting experiments,


observed that if plants are grown in a rapidly moving nutrient solution of

constant composition, the elemental concentration in the nutrient solution

could be reduced significantly (see Table 3.1) while plant growth remained

normal.
 

im4satori

Well-Known Member
Some of the issues that arise with the current formulations and use of


nutrient solutions are as follows:

1. In general, most nutrient solution formulations are not well balanced,

particularly with regard to the major elements, N and K.

2. The total elemental concentration in most nutrient solutions is higher than

can be justified in terms of meeting crop requirements. Most nutrient

element insufficiencies in plants are due to ion imbalances in the applied

nutrient solution rather than due to a deficiency of one or more elements.

3. The atmospheric demand should be a determinant of the total elemental

concentration of a nutrient solution as well as a factor in determining the

frequency of application (the higher the atmospheric demand, the lower

the element ion concentration should be in the nutrient solution with

increased frequency of application).

4. There is justification for designing the nutrient solution delivery system

so that only water can be applied, particularly during periods when the

plant atmospheric demand is high. Also being able to easily change the

dilution ratio during the delivery of a nutrient solution would be a very

useful factor.

5. The concentration of P in most nutrient solution formulations is about

twice that needed and may be the primary cause for some plant nutrient

insufficiencies among the micronutrients Cu, Fe, Mn, and particularly Zn.

6. The concentration of N in a nutrient solution may be the primary factor

determining fruit yield and quality (the higher the N, the lower the fruit

yield and poorer the fruit quality). In general, the N content of a nutrient

solution should be at the lower end of the recommended formulation

amount and should be adjusted based on atmospheric demand — the

higher the demand, the lower the N concentration in the nutrient solution.

7. The ratio between K and Ca in a nutrient solution is probably a major

factor determining fruit yield and quality. That nutrient solution elemental

ratio for most crops should about 1 to 1.

8. The use of chelated micronutrients may be the primary cause for deficiencies

of the micronutrients Cu and particularly Zn in plants.

9. Insufficient Zn in most nutrient solution formulations may be the primary

cause for low Zn levels in the plant. It is recommended that the Zn amount

be double that specified in most nutrient solution formulations. It should

be remembered that high P in a nutrient solution will inhibit Zn uptake

and distribution within the plant. The use of chelated Fe is also a contributor

to lower Zn uptake and distribution within the plant.

10. The inclusion of NH4-N in a nutrient solution formulation can enhance the

uptake of NO3-N, which can be either beneficial or detrimental. The amount


of total N in a nutrient solution formulation can be reduced by 10 to 20%

if 5% of the total N in the nutrient solution is NH4.

The Nutrient Solution 115

11. The adjustment of the pH of a nutrient solution to a particular point is

unjustified unless the pH is outside the desired range between 5.2 and

6.5. It should be remembered that the pH in the immediate area around

plant roots is determined by the roots themselves.

12. The adjustment of a nutrient solution to a particular EC is probably not

justified unless there is a compelling need to restrict water and nutrient

element uptake.

13. The accumulation of elements as precipitates in the rooting medium,

whether the medium is inorganic or organic, can have a significant effect

on the plant’s nutrition with time. Therefore, reducing the concentration

of most elements is justified, particularly Ca, Mg, P, S, and Mn, in the

nutrient solution being applied with time.

14. The requirement for leaching a rooting medium due to the accumulation

of unused elements can be significantly reduced by carefully adjusting the

nutrient solution formulation and frequency of application as well as having

the ability to apply only water for meeting high atmospheric demand.

15. An EC measurement of the solution exiting the growing medium or that

within is used to determine when the rooting medium requires water

leaching. That requirement for leaching should be viewed as a warning

signal that the quality of nutrient elements being applied at greater than

that required by the crop. This leaching requirement can be significantly

reduced if greater care is used in formulating and applying a nutrient

solution — the ideal is that no water leaching is required. An elemental

analysis of exiting or retained nutrient solution will indicate which elements

are accumulating, providing guidance in reformulating the applied nutrient

solution in order to minimize this accumulation.

16. The reuse of a rooting medium can pose a problem since that medium

will start with a significant nutrient element charge from the accumulation

of nutrient elements as precipitates that can not be removed by leaching.

17. In a closed nutrient solution system, the nutrient solution must be filtered

and sterilized between applications.

18. A nutrient solution should be assayed for its elemental content when

initially made to ensure that all the elements are within the specifications

of the formulation. Errors in selecting and weighing ingredients and mixing

when preparing stock solutions can be easily made, and the malfunctioning

of dosers (see Figures 7.4-1 and 7.4-2) is not uncommon.
 

im4satori

Well-Known Member
For most of the commonly used hydroponic growing systems, the cycling


of water and nutrient element availability are not easily controlled. As a

nutrient solution is introduced into the growing medium, three things occur.

Plant roots absorb the water and nutrient elements in the nutrient solution

at varying rates (Bugbee, 1995), water and nutrient elements not absorbed

begin to accumulate in the rooting medium (Jones and Gibson, 2002), and

some of the applied water and nutrient elements leach from the rooting

vessel. The result is a continuously varying rooting environment that can

adversely affect plant growth. This is one of the influencing factors that is

not being adequately addressed by those engaged in hydroponic system

research and development. Geraldson (1963, 1982) has addressed this problem

in his research on the effect of quantity and balance of the nutrient

elements on the growth of field-grown staked tomatoes. This basic concept

is being used by Jones and Gibson (2002) in their development of the Aqua-

Nutrient growing method and is the basis for a commercial product called


the “EarthBox” (Figure 11.11).
 

Chunky Stool

Well-Known Member
I have more experience with organics.

I recommended the dynagro because the op was using a one part and the foilage pro would work better.

It is higher in N but I am a fan of green to the end.
View attachment 3876563
This is one of mine.
Is your soil hot enough to finish them green? By the end of my cycles, I'm always adding tea and/or liquid organic nutes. I like the control, so I avoid top-dressing.
 

im4satori

Well-Known Member
There also exists a balance among the major cations, K, Ca, and Mg, and


if these elements are out of balance with each other, then Ca uptake and

movement can be impaired. The author has observed BER-affected fruits when

there were visual leaf Mg-deficiency symptoms. The presence of NH4 in the


nutrient solution, if greater than 10%, can significantly increase the incidence

of BER (Hartman et al., 1986).

Phosphorus excess is more likely to occur than its deficiency, and its excess

(greater than 1.00% of the dry weight) in recently mature leaves can result in

Zn deficiency (Jones, 1998a).

The source of Fe can not only affect its uptake but can significantly impact

the plant. For example, the chelate ethylenediaminetetrateacetic acid (EDTA)

Figure 11.25 Symptoms of blossom-end rot (BER) on tomato fruit. Normally,

the symptom — browning (decay) of the blossom end of the fruit — occurs

early in fruit development. Such fruit should be removed when first observed.

BER fruit will early turn red.

Hydroponic Cropping 215

form of Fe is not recommended since EDTA is toxic to the plant (Rengel,

2002). The chelate diethylenetriaminepentaacetic acid (DTPA) form of Fe is

the accepted chelated form since DTPA toxicity is thought not to exist. Rengel

(2002) observed that the inclusion of Fe-EDTA in a nutrient solution resulted

in reduced uptake and translocation of the micronutrients Cu and Zn within

the plant. It is not known if the DTPA form of chelated Fe will have the same

effect on these two micronutrients. Other chelated forms of Fe, HEEDTA, NTA,

and EDDHA, have been used, but to a lesser degree than either EDTA or

DTPA. Several inorganic forms of Fe have been found suitable as Fe sources

in nutrient solution formulations, such as iron ferrous sulfate, FeSO4•7H2O;

iron ferric sulfate, Fe2(SO4)3; ferric chloride, FeCl3•6H2O; and iron ammonium

sulfate, FeSO4(NH4)2SO4•6H2O.


The author has frequently observed low Cu and Zn contents in tomato

leaf samples submitted for analysis and interpretation. The questions that need

to be answered are, “do these low levels reflect an inadequate amount of Cu

and Zn in the nutrient solution,” or “is it a factor related to cultivar adsorption

capacity, or is it the influence of the Fe chelate in the nutrient solution on

Cu and Zn adsorption?” My best guess would be the influence of the presence

of the chelate in the nutrient solution. In earlier experiments, I have found

that if the Fe source was an inorganic one (see pages 57 and 398), low Cu

and Zn leaf contents were not frequently observed.

Under varying environmental conditions, the nutrient element
 

im4satori

Well-Known Member
Calcium (Ca) Chlorosis generally begins at tips and margins of young


leaves, progressing between the veins followed by necrosis,

leaf tips and margins turn brown to black, the growing point

emerges slowly, may be deformed and die, emerging flowers

and small fruit abscess, apical decay of the fruits (BER).

Symptoms not known, excess K will result in a possible Ca,

and more likely induced Mg deficiency


Magnesium (Mg) Chlorosis starts between veins of older leaves and leaves

become yellow, intervein chlorosis of the older leaves,

possible appearance of BER in fruit symptoms not known,

excess may influence the function of K and Ca


Phosphorus (P) Stunted plants with thin stems, abnormally dark green plants


with reddish or purplish pigmentation, sometimes chlorosis

occurrence on the older leaves no specific symptoms for this

element as high P will result in possible micronutrient

deficiency, other either Fe and Zn, Zn being the one most

likely to occur
 

im4satori

Well-Known Member

Nutrient Element Accumulation in the Rooting Substrates


With each addition of nutrient solution (whether in an ebb-and-flow or drip

irrigation system) to a rooting substrate, an accumulation of elements occurs.

A portion of this elemental accumulation can be leached with water since a

portion of some elements continues to exist as ions. That which can not be

leached from the substrate with water exists as precipitates, mainly a mix of

calcium phosphate and calcium sulfate. In the process of precipitate formation,

other elements, primarily Cu, Fe, Mn, and Zn, will be either adsorbed on the

surface of the precipitate or exist as compounds within the precipitate. After

several months of use in an ebb-and-flow
 

whitebb2727

Well-Known Member
Is your soil hot enough to finish them green? By the end of my cycles, I'm always adding tea and/or liquid organic nutes. I like the control, so I avoid top-dressing.
That run it was.

I've gone to simpler is better. I run a couple batches of soil. I alternate. One cooking while I grow.

I have chicken, horse, rabbit and cow manure. All organic fed. I compost the manure along with leaves and other stuff like the stalks left after harvest out of the veggie garden.

I also have a worm bin.

I just mix some compost, worm castings and manure compost and let cook. Rabbit manure can be used fresh.

I add a few other things like kelp meal, and a little garden tone that has various meals in it.

My plants love it. If they need a little something I throw a handful of vermicompost and castings with a pinch of garden tone and mix in the top inch of soil and water in.

Easy peasy.
 

whitebb2727

Well-Known Member
read that last one again and tell me more about how you should have all that calcium and sulfur
Why not back off a little. I see you have plenty of book knowledge. That's a good thing but sometimes simpler is better.

You are kind of over complicating this.

Its great knowledge but its too much at one time for a.new grower.
 

im4satori

Well-Known Member
the author has found that these


substrates after several months of use contain substantial quantities of P, K,

Fe, and B; moderate levels of Ca and Mg; and low levels of Mn and Zn (Table

11.17). The high P, Fe, and K levels in the perlite may explain why plant

levels of Zn and Mg are frequently low (P and Fe interfere with Zn uptake

and K with Mg uptake), and Mn levels are high (P enhances the uptake of

Mn). It may be that the uptake of Ca is restricted by high K, which could be

a factor in the occurrence of BER in fruit. Although cultivation may begin

with a nutrient element-free substrate (such as perlite or rockwool), with time

the substrate becomes a significant source of nutrient elements, and the plant

begins to respond to the elements accumulated in the substrate rather than

those applied in the nutrient solution. For example, I advised a hydroponic

tomato grower after about 5 months of growing in a gravel ebb-and-flow

system that a nutrient solution made up of only KNO3 and borax would be


sufficient to sustain plant growth. This proved to be true as there were sufficient

quantities of the other essential elements that had accumulated in the gravel

as precipitates. Plants are able to utilize this source of nutrient elements since

the root rhizosphere is strongly acidic, dissolving a portion of the precipitate

and releasing the elements for root absorption as plants do when grown in

soil (Jones, 1998b). This nutrient element accumulation poses a significant

factor when the growing substrate is reused, which can significantly influence

the nutrient element supply and balance in succeeding crops.
 

im4satori

Well-Known Member
I could continue but I think this is enough

sorry to the original thread starter for all the banter\

clearly theres a relationship between K:Ca:Mg as well as many other elements

the ratio between the three is more important than the amount
 

Chunky Stool

Well-Known Member
I may just start using recycled dirt for my inside grows. Hell I always get bugs anyway.
I've got a giant pile cooking now. I threw some alfalfa meal on it a couple of weeks ago. It will be cooked as hell by spring.
Odd tidbit: My favorite plant in the current run was a seedling I found in the pile last summer. Definitely a female, I'll call this strain "Lucky". She looks so good I even took cuttings! It'll be a major bummer if the buds aren't fire. No idea how long she will take to flower. Could be fun!
 

im4satori

Well-Known Member
Why not back off a little. I see you have plenty of book knowledge. That's a good thing but sometimes simpler is better.

You are kind of over complicating this.

Its great knowledge but its too much at one time for a.new grower.
it was requested within the thread

to show the correlation between the elements
 

jronnn

Well-Known Member
jronnn, do you have anything to tell us at this point?
not really, idk who did and didnt see the pics i posted and i want to correct the problem, not switch nutes i really didnt get an answer on what to do other than run away from the nutes im using even though they seem to work for everyone else who uses them
 
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