Guide to Nutrient Deficiency or Toxicity

Grenier5413

Well-Known Member
Sorry guys my phone broke. Just got back. The only tester I have is for pH and basic neuts. Considering I did nothing to the soil practically I'm sure your right.
 

Kidbruv

Well-Known Member
So my friend is growing a plant with identical genetics to mine (clones) in almost identical conditions outdoors. He sent me a pic today to compare how far into flowering we both are and I noticed that his leaves were very "veiny". Overall his plant is very healthy with just the occasional lower yellow leaf.

I don't know if this is anything other than young leaves (because the older ones around it don't seem to have that same veininess) or just pics taken in different lighting, but figured it was worth asking. Possible early magnesium deficiency?

First pic is his plant, second mine...
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dickiefickle

Active Member
So 99% of the times I come in here to see what people are up to and check what forum threads I can throw some advice in, its plant issues.

"theres yellowing" or "leaf is dry and brittle" or "OMG SPOTS!"

so instead of using the 'cut and paste' tools, over and over all day, like I feel I have been, i figured id start this. Theres other stickies on here, but apparently people either dont read them, or cant connect their plant's issues to what those authors are describing.

*NOTE: to make sure your plant is getting what it needs, keep soil pH to 6.5 and 5.8 in hydro, otherwise, the nutes can be there, but the roots cant take them in*

Also, make sure if you notice a deficiency, please please PLEASE, dont drown the plant in that chem to save the day. your not superman. feed the plant. dont suffocate it! Slow changes are the best way to make sure you dont go from a deficiency to an abundance, and the inevitable burn.

So lets start with the basics, NPK.

Nitrogen: This element is everywhere, your breathing it in right now! For your :leaf: plants, its key in the vegetative growth. It stimulates and powers the formation of leaves, strengthens the stems, and helps the chlorophyll production.

An abundance of this is rare during vegetative, but it happens with new growers that think more ferts = more plant (and your right, but to a limit!). To tell if you have an abundance of nitrogen, simply look at the plant. You want green leaves, but not a dark green -> black color.
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A deficiency of this causes yellowing of the leaves. its common during vegetative simply because the plant is using it up just as fast as your putting it in. It also happens during flowering sometimes because most flowering fertilizers contain little or no nitrogen, as this is not a key nutrient in that phase of the plant's life cycle.
Usually the deficiency will be noticeable on the lower part of the plant, on the older leaves. then, as it progresses it will move upwards towards the newer growth.
*unlike a magnesium deficiency, nitrogen def will start from the tips and works its way inward* (ill get to mag def later). Most of all yellowing of leaves is caused by this, and it will stunt growth severely!
View attachment 1894154

Phosphorus (P):
The 2nd element in our NPK ratio and just as important! So, whats it do? Root growth. This nutrient is essential for the roots to thrive, and big roots can feed big plants. Its key from the time the seed hits the dirt. it speeds up germinating, it supports vegetative growth by providing the roots to support it. Its a MAJOR nutrient in reproductive stages of the plant (yes, flowering). No phosphorus, no buds.

Abundance: too much can affect plant growth by suppressing the intake of iron, potassium, copper and zinc. (wierd huh? but yea, phosphorus abundance is generally followed by a zinc deficiency)

[if someone has a pic of P abundance lemme know and ill add it in]

Deficiency: Didnt i go over this? slow growth! slow leaf growth, slow root growth, slow germination of seeds, slow bud production, the edges of eaves will be brown. Even fan leaves, the plants solar cells, will be affected by this, turning them to a dark green, purple and blue color. (not the kind of purple you want.)
*Deficiency of this can be caused by low temperatures - below 50F/10C

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Potassium (K):
a.k.a. potash, this nutrient is key for the usage of carbs/sugars. This is key for sturdy/thick stems, small bushy plants and disease resistance. Its needed for all stages of plant growth, especially bud formation.

Abundance: this is pretty rare to notice, excess potassium usually isnt absorbed by the plants but can mess with levels of magnesium, manganese zinc and iron. This in turn leads to salt damage acid fluctuations and possibly a calcium deficiency

Deficiency: this has yellowing of leaves, from outside in, but with a dark green center vein, and curling of leaf tips, this is mistakenly diagnosed as nitrogen def or iron def a LOT. Stems and branches will be weak, easily broken. the plant may also stretch. *too much sodium (NA) can cause a potassium deficiency.

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Ok so thats the basics. Now on to the trace elements. Wonder why they call them 'trace' elements? and why you dont see ratios or percentages on how much of them to use? its becuase you dont want too much of them. you want them, but very very little.

Magnesium (Mg): this is a component of the chlorophyll molecule, it works with enzymes in the plant. Magnesium helps support healthy veins, and leaf production.

Abundance: Excessive levels will create a toxic amount of salts, that will inturn kill your leaves, and lock out calcium.

Deficiency: This is pretty easy to notice, green veins but fully yellow leaves. leaf tips can discolor and curl upwards. leaf edges can feel dry and crispy. the necrosis on the leaf will start at the edges, work all the way around the leaf. the tips will twist and turn, then the leaves will fall off without withering. *mag def is common with too acidic pH*
heres 3 pics of early-med-late deficiencies of magnesium:

early:
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later:
View attachment 1894203View attachment 1894204

Zinc (Zn): Zinc does a little of everything, helps in plant size production of leaves, stalks, stems branches... Essential component in enzymes and growth hormones. its key in the formation of chlorophyll. Plants that have a healthy amount of zinc are more resistant to drought.

Abundance: this is rare. it can cuase wilting and death in extreme cases. but usually, this wont happen.

Deficiency: Spotting, bleaching of spots between veins (commonly confused with iron/mag def). Usually appears on older leaves first. It will affect the tips of growing points on the plants. Small crops due to zinc def is common. Pale/greyish leaves will be apparent (check for a nice shine to the leaves, if they lack some luster, they might lack zinc!)

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Calcium (Ca): Strong bones, duh. no really. strong cell walls, cell division, and root growth (mostly the newer root hairs). Helps absorbtion of K. Calcium moves slow, and tends to concentrate in roots/older growth.

Abundance: Too much can lead to other deficiencies. this can be caused by clay soils, unbuffered coco/humus, or excessive lime in the soil.

Deficiency: First visible in newer growth, leaf tips will die, tips may curl, growth is stunted. there will be a weakness in stems/branches. underdeveloped roots, and bacteria problems can arise. *can be cuased by too much potassium/nitrogen* calcium deficiency is commonly mistaken for over ferting. its key to notice in these pics that early stages of deficiency appear in the serrated edges/tips of the leaves, but its not just a death/necrosis, its a small circular spots of death, not just burn marks. young leaves will develop dwarfing, a strap-like shape, and shoots stop growing and thicken.
View attachment 1894224

later, it appears all over the leaf, and becuase its usually on the older growth, many people think its bugs. (noobs.... do you see bugs anywhere?)
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Iro


happy growing!
This could be useful with some pictures
 

Jerro

Member
Hello everyone,

2x 1000 watt SolarMax/VEG - Metal Halid- Air cooled 4 feet Away running @ 75%

Temps are have been @ 68-76 most grow
except for a few heat waves but never over 85 Degress for Longer then 4 hours.
Humidity has been 50-60 except a few days they dropped to 25 I added a humidifier and have kept it at 50-60%
Running light 24/7
Rapid rooters starting plug.

Air circulation is good fan blowing over the top and two others moving air back to the carbon scrubber.

DWC - 55 Gallon 6 pot system- cultured soultions under current @ 67 Degress
R/O water - system is currently at 6 PH -Stable
40 Gallon Reseivor - 5.7 PH currently - 67 Degress
40 days since planted seeds

I have co2 setup also and ran it for a few days, my room isn't completely sealed and it is escaping so I will seal everything up and start to run that this week. The growth difference is huge it was amazing anyways let me get to the rest..

Nutes: cultured soultions veg a, veg- b @ at half of recommended strength, UC roots, cal-Mag half strength, when I topped the first time the stem I cut was hollow. The system is at 210ppm and the Rez is at 420ppm (EC500 Scale)


I was having N toxicity so I drained everything out and cleaned everything throughly with hydrogen peroxide. I had ph fluctuations (faulty Ph meter) in the beginning and the first water change I did I didn't have a transfer pump so alittle build up was left behind which most probably caused N toxicity. I have topped five of them twice and one three times.

Everything seems to be normal now, but I want to make sure her growth is normal as this is my first grow and havnt seen any other plants grow. Also my rapid rooters has green alge growing on top.. How do I treat this?? Do I spray hydroton peroxide and then cover it up so no light gets shined on it? Thank you all for your help!!
 

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Roger A. Shrubber

Well-Known Member
at first glance i would say something is eating it. looks like leafminer damage, which is actually the small larvae of several different pests that haven't emerged yet. spraying isn't very effective, as they're inside the plant. do you have any insects like small flies around your grow room? using yellow sticky traps helps, and i've found that watering with a half strength dose of spinosad if they get bad helps knock them down a lot. they aren't the same as fungus gnats, but if fungus gnats like the conditions, so will they.
 

HydoDan

Well-Known Member
at first glance i would say something is eating it. looks like leafminer damage, which is actually the small larvae of several different pests that haven't emerged yet. spraying isn't very effective, as they're inside the plant. do you have any insects like small flies around your grow room? using yellow sticky traps helps, and i've found that watering with a half strength dose of spinosad if they get bad helps knock them down a lot. they aren't the same as fungus gnats, but if fungus gnats like the conditions, so will they.
I was just reading about leaf miners last night and now here they are.... good call
 

Roger A. Shrubber

Well-Known Member
there are at least 4 different insects that can be called "leafminer" in that stage, some travel around, some just sit and eat one spot. they don't have spots anywhere else because the larvae are close to where you see the damage. the best thing to do if its just one or two leaves is cut them off and dispose of them.
 
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