Soil NPK?

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MechaniMan

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How does soil npk equate to npk the plant will absorb from the soil?

Example soil is
N=.09%
P=.05%
K=.07%
 

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in simple terms , cannabis will only absorb the food they need and by simple observation , one will learn how to interpret deficiencies and over feeding

finding a happy balance of nutrients , the proper grow medium , lighting , water , and other environmental conditions are all different

All Hydro 101SELECTIVITY OF PLANT NUTRIENT ION UPTAKE
CATEGORIES

The interactions between mineral cations and anions are well understood by chemists, but often overlooked by horticulturists when applying fertilizers to tailor the growth of a specific plant variety.

You may have heard the phrase “It’s not what you eat, it’s what you absorb,” a phrase that applies equally to the uptake of essential nutrients by plants. Application of an essential plant nutrient does not always mean that the plant will be able to uptake that mineral and then move it through the vascular system into the plant tissues.

The availability of plant nutrients is in fact dictated by the form of mineral, environmental temperature, humidity, photosynthesis, pH of the root zone, and most importantly the relative concentration of each mineral in the nutrient solution. It is the balance of these minerals that is often forgotten when growers are formulating plant nutrient recipes and adding supplements to reach specific targeted mineral compositions.

There is a well-known system that classifies essential plant nutrients into “macro” and “micro” categories based on their concentrations in the plant tissue. Less understood is the relationship of the electrical charge of the individual ions and how it affects their bioavailability to the plant. Ions exist as either positively charged (cations) or negatively charged (anions) depending on the balance of electrons (negative) versus protons (positive).

It is the strength of the ionic charge that will affect the movement of the ions into and out of the plant. By understanding the strength of the positive or negative charge of essential plant nutrients, we can begin to comprehend the selective ion uptake mechanisms of a plant’s physiology. The table below shows the elemental forms of plant nutrients and their ionic charges in the forms that are available for plant uptake.

essentailn
The movement of ions into plant roots occurs by both active and passive transport. Passive transport means that the ions are carried with the uptake of water into the plant without energy from the plant. The water movement factors that affect passive transport are temperature, humidity, photosynthesis rates, concentration of ions in solution versus within the plant cell, and plant transpiration rates based on stage of growth. Active transport requires energy from the plant and ion movement is determined by competition between ions based on their individual charge. The monovalent ions (single charged) are moved into the plant more easily than divalent ions (double charged), while divalent ions are taken up more easily than trivalent ions (triple charged). This means that the plant will accumulate more potassium (a monovalent ion) than calcium and magnesium (divalent ions) due to the difference in their charge.

Plants typically maintain a negative interior (inside the plasma membrane) relative to the exterior. The slightly negative state of the cell interior and the environment must be maintained and, thus, is related to ion uptake. When there are more cations than anions present, the overall charge becomes excessively positive, and an increase in anions or a decrease in cation uptake occurs to restore physiological conditions. For example, an excess of ammonium (NH4+) cations decreases the uptake of potassium (K+), calcium (Ca2+), and Magnesium (Mg2+). The same relationship exists for anions – excess anions lead to a lower uptake of anions or an increase in cations to balance the cell’s charge. If nitrate (NO3-) is the major anion in excess, then the uptake of cations such as potassium (K+), calcium (Ca2+), and Magnesium (Mg2+) will increase to compensate for the overall negative charge caused by excess nitrate levels.

essentailnPic2
 
in simple terms , cannabis will only absorb the food they need and by simple observation , one will learn how to interpret deficiencies and over feeding

finding a happy balance of nutrients , the proper grow medium , lighting , water , and other environmental conditions are all different

All Hydro 101SELECTIVITY OF PLANT NUTRIENT ION UPTAKE
CATEGORIES

The interactions between mineral cations and anions are well understood by chemists, but often overlooked by horticulturists when applying fertilizers to tailor the growth of a specific plant variety.

You may have heard the phrase “It’s not what you eat, it’s what you absorb,” a phrase that applies equally to the uptake of essential nutrients by plants. Application of an essential plant nutrient does not always mean that the plant will be able to uptake that mineral and then move it through the vascular system into the plant tissues.

The availability of plant nutrients is in fact dictated by the form of mineral, environmental temperature, humidity, photosynthesis, pH of the root zone, and most importantly the relative concentration of each mineral in the nutrient solution. It is the balance of these minerals that is often forgotten when growers are formulating plant nutrient recipes and adding supplements to reach specific targeted mineral compositions.

There is a well-known system that classifies essential plant nutrients into “macro” and “micro” categories based on their concentrations in the plant tissue. Less understood is the relationship of the electrical charge of the individual ions and how it affects their bioavailability to the plant. Ions exist as either positively charged (cations) or negatively charged (anions) depending on the balance of electrons (negative) versus protons (positive).

It is the strength of the ionic charge that will affect the movement of the ions into and out of the plant. By understanding the strength of the positive or negative charge of essential plant nutrients, we can begin to comprehend the selective ion uptake mechanisms of a plant’s physiology. The table below shows the elemental forms of plant nutrients and their ionic charges in the forms that are available for plant uptake.

essentailn
The movement of ions into plant roots occurs by both active and passive transport. Passive transport means that the ions are carried with the uptake of water into the plant without energy from the plant. The water movement factors that affect passive transport are temperature, humidity, photosynthesis rates, concentration of ions in solution versus within the plant cell, and plant transpiration rates based on stage of growth. Active transport requires energy from the plant and ion movement is determined by competition between ions based on their individual charge. The monovalent ions (single charged) are moved into the plant more easily than divalent ions (double charged), while divalent ions are taken up more easily than trivalent ions (triple charged). This means that the plant will accumulate more potassium (a monovalent ion) than calcium and magnesium (divalent ions) due to the difference in their charge.

Plants typically maintain a negative interior (inside the plasma membrane) relative to the exterior. The slightly negative state of the cell interior and the environment must be maintained and, thus, is related to ion uptake. When there are more cations than anions present, the overall charge becomes excessively positive, and an increase in anions or a decrease in cation uptake occurs to restore physiological conditions. For example, an excess of ammonium (NH4+) cations decreases the uptake of potassium (K+), calcium (Ca2+), and Magnesium (Mg2+). The same relationship exists for anions – excess anions lead to a lower uptake of anions or an increase in cations to balance the cell’s charge. If nitrate (NO3-) is the major anion in excess, then the uptake of cations such as potassium (K+), calcium (Ca2+), and Magnesium (Mg2+) will increase to compensate for the overall negative charge caused by excess nitrate levels.

essentailnPic2
Ah, so this kind of explains why when my animals piss on my plants(damn neighbors dogs) I can rinse the ammonium away before it f's my plant up with all that extra nitrogen because the nitrite has a negative charge and won't "stick"?
 
Ah, so this kind of explains why when my animals piss on my plants(damn neighbors dogs) I can rinse the ammonium away before it f's my plant up with all that extra nitrogen because the nitrite has a negative charge and won't "stick"?





you catch on quick Amigo
 
Well if that doesn't answer the question I don't know what will, thank you!

I'll have to read that about 20 times over.
I can see I have some more research to do.
 
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I'll tell ya, that kinda puts me at ease. My plan is to use stronger p-k fert. to compensate for the slow feed soil when I get to bloom. Not go overboard by any means but to kinda overpower the nitrogen slow release. It sounds as though it'll work according to that. If I up the phosphorus and potassium in bloom then I should not have to worry about excess nitrogen. If there is any. The plant will adjust its nitrogen uptake to compensate for the increased p-k.
 
I let MG deal with my NPK. My plants and Veggies love the soil.
 
I let MG deal with my NPK. My plants and Veggies love the soil.
That's what that is, miracle MG veg & herb moisture control. I don't have to water much and I account that to the soil. I'm @ week 5 veg today and will update my grow thread later on today. They are looking great. A lot better than a good portion of the plants I see at week 5 surfing around on the internet.
 
Awesome. Yeah I don't use the moisture control because I worry about to much moisture.
I use the MG Twice As Big and add 30% Perlite for drainage.
Glad to see you have them dialed in. MG is a good soil. I have used it for yrs with no problems.
 
Curious about Urea (Nitrogen). Should it be counted as cations or anions?

Supposedly in soil it converts to ammonium nitrate rapidly in soil (which then gets converted to nitrate), but not so sure about water. I have a 6% solution I use on my okra plants to get higher nitrogen than the standard nutes provide. Wondering if I could use it in hydro.
 
So it's a maybe : ) If the PH falls, the plants like it, otherwise no.
 

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