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HIGHway's Plant Nutrient Deficiency Chart

As I write this, I hope it helps as many people as possible. I’ve fielded question after question and have helped a lot of people through some really bad deficiencies, almost everything under the sun.

I will start with the mobile elements, or the “Main nutrients” of Nitrogen, Potassium, and Phosphorous. Next will be Magnesium, Sulphur, and Calcium. Next is what we call the “Trace Elements” of Molybdenum, Copper, Zinc, Boron, and Manganese and Iron. These are the 12 elements that Cannabis needs to survive, in order of importance.

The “Trace Elements” are only needed in very small quantities, and in if present in too large a quantity, can lock-out the other elements masking as many other problems. Some will even fool you by masking as Over fertilization, or another deficiency.

Ok, Let’s start with some descriptions of what the elements do for the plant, and why they are each important. We’ll start with the mobile elements on Nitrogen, Phosphorous, and Potassium.

Nitrogen:
Nitrogen is a key Element in the production of Amino Acids, which are the building blocks of Proteins. Many plant hormones contain Nitrogen as well as Chlorophyll, DNA and RNA (Genetic materials), and a myriad of enzymes that help control and regulate growth.

Phosphorous:
Phosphorous is used for plant energy by being assimilated into molecules called Adenosine-tri-phosphate, or ATP. This molecule is necessary for any plant activity that requires energy such as root growth, flowering, respiration (yup, plants breathe), and vegetative growth.

Potassium:
Potassium serves to aid in the process of photosynthesis, nutrient uptake, respiration, and is a key to sturdy stems and disease resistance. Having an adequate supply for the plant early in it’s life stage will keep your seedlings from falling over.

OK, now that the main three elements have been covered, lets get to the next three important elements of Calcium, Magnesium, and Sulphur.

Calcium:
Calcium is an important co-enzyme in the production of fatty acids, cell membranes, and is necessary for normal mitosis/cell division. I’ve yet to see a Calcium deficiency, and it is the only element that I do not have a picture of.

Magnesium:
Magnesium is analogous in plants as Iron is to Humans. In humans, Iron is the central atom in the structure of the Hemoglobin molecule, and that what the red blood cells use to hold and deliver Oxygen throughout.

Chlorophyll is of the same structure as Hemoglobin, except that it has a magnesium atom in place of the Iron atom found in Hemoglobin. Chlorophyll is how plants make sugars to feed the process of building ATP through the Krebs cycle.

Sulphur:
Biotin and Thiamine as well as a myriad of other plant vitamins that they synthesize themselves that contain Sulphur. It is an important element in the structures of amino acids and proteins, and is needed for normal plant respiration and metabolism of sugars and other compounds.

Well, that seems to leave us with the six trace elements of Boron, Copper, Iron, Manganese, Molybdenum, and Zinc. None of these are needed in large quantities, but are none-the-less an important tool in the mobilization of molecules, the breakdown of molecules, as well as the transfer of energy in plant processes. Chances of seeing anything but an Iron deficiency are slim, but when pushing the envelope with HID’s and CO2 enrichment, they will pop up from time to time. Most are seen, if ever, in outdoor grows.

Mobile Nutrients:
Now lets get into the picture part of this article

Nitrogen:
We’ll start with a Nitrogen deficiency. As you look at the photograph, (missing) you’ll notice that the large fan leaves from the bottom up are yellowing and turning purple-ish. Plants suffering from this deficiency are distinct in their pattern of yellowing from the older leaves, and leaving the top parts of the plant green, as Nitrogen is the most mobile element. Plants exhibiting yellow lower leaves and green top growth and wilting in well-aerated soil that is not over-watered are easily diagnosed as a Nitrogen deficient plant.

Feeding with a high N fert will clear it up, like an emulsion of fish at 5-1-1.

Phosphorous:
Phosphorous deficiencies are distinct as well. Purple stems, stunted growth, and leaf stems that are purple in the veins are a sure sign of a Phosphorous deficient plant. Leaves will also tend to be smaller and dark green, and may or may not include nectotic patches. Bud size will be smaller and underdeveloped, as will the root-mass I’ve included several photographs of this deficiency for you to aid yourself in how it looks in different phases of growth.

A good all-around fertilizer like Peter's 20-20-20 will clear this up.

Potassium:
Potassium deficiencies are identified simply by the necrosis of the larger fan leaves on the margins and necrotic patches on the leaves as well. Leaves will eventually turn yellow, then brown and die off. Most of the plants that show signs of a Potassium deficiency are going to be the tallest and best looking plants you have.

Again, feeding with a good all-around fertilizer will clear it up as well. You can also use wood ashes and water them into your soil to fix this. You'll need to replace your soil's holding capacity of Potassium, and have a surplus before it will become available to the roots again.

Minor Nutrients:
Magnesium A magnesium deficient plant is identified by intervenial chlorosis, necrosis, and eventually a lockout of plant nutrients. The problems starts at the bottom of the plants and works it’s way up. I’ve included several pics of different stages and signs of a magnesium deficiency. The first one is a Mg deficient plant in flower, and the second two are of the leaves to show what I mean by Intervenial Chlorosis. Treating with an Epsom salts mix will clear this right up.

Sulphur:
I looked for hours to find this picture, and if you ever see this in your plants, then you can be assured that you have this deficiency. Look for yellowing starting from the top of the plant down, including the veins of the leaves. Treating this is the same as you would treat a Mg deficient plant, use Epsom salts.

Calcium:Well, I have found only 2 pictures of this deficiency, and you are more likely to be hit by lightning than ever experience this problem. I do not even know how to describe it other than that it’s going to stunt the plant’s growth, and will be present in soils that are too acidic, or in a Hydroponic system that uses Distilled water and noo or little added Calcium. You will notice in the pictures that the leaves have necrotic lesions on them, but do not use this as a method to diagnose your problem, instead use the information to do that, as this masks as a K deficiency as well as Mg (a little), and Iron.

Trace Elements:

Boron:
This is a rare occurrence and is exemplified by small gray or necrotic patches on the growing shoots which eventually die.

Fixing this is done easily by applying a foliar spray of eyewash containing Boric Acid.This picture is not really the best IMO, but it shows a gray patch on a leaf that is indicative of what to look for. This will most likely occur in outdoor grows.

Copper:
A copper deficiency is commonly mistaken for an overfertilazation problem, but it is set apart by the growing tips dieing off first along with the crispy leaves. The new shoots will die from the tips and margins first, often going brown or even white before they die.

A commercial fungicide containing Copper applied foliarly will clear it up, but the damaged leaves may never recover.

Iron:
An Iron deficiency will mask a Magnesium deficiency. If you look at the newer growth, that will be where the plant exhibits the intervenial chlorosis typically differentiating it from a Magnesium deficiency. Notice how the top of the plant is exhibiting IVC and the lower part is unaffected. This first picture I show I found as a zinc deficiency. I’m placing it here as an Iron deficiency as the picture I will post later will exhibit a true zinc deficiency.

Manganese:
A Manganese deficiency exhibits a general chlorosis, followed by yellowing patches and necrotic patches between the veins of the larger fan leaves. This is very obvious in the following pictures.

Molybdenum:
A Molybdenum deficient plant will Exhibit yellowing necrotic leaves from the tips inward, with necrotic lesions present from the tips inward. It occurs on the middle of the plant, distinguishing itself. I also may spread to the rest of the plant if not stopped, and can kill your plant.

Fritted Trace Elements may be added to your soil mix as you prepare it for planting. A good Hydroponic nutrient should contain ample micros to get your plant through it’s lifecycle.

Zinc:
A Zinc deficient plant is obvious from the wispy new growth with twisted leaflets at 90°. There is also intervenial chlorosis at the top of the plant that is commonly confused with an Iron deficiency. Notice in this picture that the older grown leaves are relatively unaffected and healthy

Other Persistent Problems:
pH:
Improper pH can cause an abundance of problems that you might easily confuse with other problems or deficiencies, and it may also be the cause of the deficiencies in the first place. PH in soil is best in the range of 6 up to 7.5, and in a Hydroponic system it’s best at 5.2-5.8. The following chart exemplifies this:

The following pictures are examples of what to look for in a plant, and to see a what a pH shift out of the proper range will or might look like.

Over watering/lack of Dissolved Oxygen to the roots:
The following yellowing at the bottom with droopy leaves pictures of plants illustrates persistent over watering problems. It becomes obvious when you look at the following pictures

Over Nitrification:
The following pictures show the “claw” indicative of over Nitrification. Some growers “Load” their plants with Nitrogen prior to blooming them to prepare for the stretch to follow, and that process will also increase bud production if induced a few weeks prior to blooming the plant. So, it's not always a bad thing to see..

Here is a shot of a plant with heat stress and slight over Nitrification. I should know, it was one of mine.

Radiant Heat:
There is a link in my sig that describes this problem in detail, so I’ll refer you there rather than re-post the information. I will, however post the pictures of what to look for with Radiant heat.

And, Finally, the most common problem, Too much love..

Over Fertilization:
This is a very common problem that can be disguised as an improper pH, or light burning, as well as a myriad of other problems. Here are some pictures of the problem. The first picture masks as over Nitrification, but notice how the entire leaf is curled under, not just the tip.

Here is a photo that displays many problems associated with overfert, some of which could be a simple imbalance of pH and a certain nutrient/micro lockout at the given pH. One FTE may become too soluble and cause the lockout of minor or major Nutrients.

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