Micro Nutrient deficiency Guide: Ca, Zn, Fe, S, Mn, B, Cu, Mo,

[dHetep]

Calcium (Ca) Macro Nutrient and an MIcro Nutrient. Calcium is another important element that helps the plants cell walls, cell division in making the plants stems, stalks, branches stronger, as well as contributing to root growth, mostly the newer root hairs, Calcium also helps enhancing the uptake of K in the plants roots. Calcium moves really slow within the plant and tends to concentrate in roots and older growth.

When plants exhibit a Calcium deficiency the younger leaves are the first to show it as well as older leaves. The Leaf tips will die back, the tips may curl, and growth of the plant is stunted. The plant can show a weakness in the stems and branches, as well as a under developed root system that can lead to bacteria problems with roots dying off. Having slow plant transpiration rates can aggravate the uptake of calcium. Make sure your soil isn’t very acidic, for calcium gets harder to be absorbed through acidic soils, which leads to having a plant that is deficient in Calcium. The leaf tips, edges and new growth will or may turn a yellow/brown color that happen in spots and often surrounded by a sharp brown outlined edge and then the leaf tips die back. If too much calcium is given at an early stage of growth it can stunt the growth of your plants. Having to much of calcium will also flocculate when a concentrated form is combined with potassium. The parts affected by a calcium deficiency are the roots. Stem or petiole, young or old leaves. Too much Calcium will lead to other micronutrient deficiencies. Calcium fixation is caused by many types of mediums such as: clay soils, unbuffered coco and humus. The lime tends to bond to these soils very easily. The stems of the plant will not be able to hold the plant up and will exhibit a white brown in between the veins of the leaves when having too much calcium. Also having to much potassium and or nitrogen will cause a calcium lockout.



Problems with Calcium being locked out by PH troubles Very acidic soils with excessive potassium, dry and or wet soil. Lack of calcium in the soil may cause too acidic soil. This may cause to Mg or Iron deficiency or very slow stunted growth.

Soil Calcium gets locked out of soil growing at pH levels of 2.0- 6.4 Calcium is absorbed best in soil at a pH level of 6.5-9.1 (I wouldn’t recommend having a pH of over 7.0 in soil) anything out of the ranges listed will contribute to a Calcium Deficiency.

Hydro and Soil less Mediums Calcium gets locked out of Hydro and Soil less Mediums at pH levels of 2.0- 5.3 Calcium is absorbed best in Hydro and Soil less Mediums at pH levels of 5.4-5.8 (I wouldn’t recommend having a pH over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to a Calcium Deficiency.

Solution for Fixing a Calcium Deficiency To fix a calcium deficiency you can treat by foliar feeding with one teaspoon of dolomite lime or Garden lime per quart of water, Or Any Chemical/Organic nutrients that have Calcium in them will fix a Calcium deficiency. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!) Or you can take crushed up dolomite lime or garden lime in a gallon of water and water it in the soil. 1 to 2 teaspoons per gallon of water, which will be slow acting. Garden Gypsum, which is medium absorption. Limestone, which is medium absorption, Rock Phosphate and Animal wastes which are both medium/slow absorption.

Note: Caution when using gypsum to an already acid soil (pH that is less than 5.5) can have a very bad effect on different types of plants by affecting the absorption of soil aluminum, which is poison to plant roots.

Now if you added to much chemical nutrients and or organics, (which is hard to burn your plants when using organics) you need to flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients.

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Zinc (Zn) Micro Nutrient and an immobile element. Zinc plays a lot of roles in the plants, first off zinc aids in the plants size and maturity as well as production of leaves, stalks, stems and branches. Zinc is an essential component in many enzymes as well as growth hormone auxin. Low auxin levels can be the cause of stunting of the plants leaves and the shoots. Zinc is also important in the formation and activity of chlorophyll. Plants that have a good level of Zinc, can handle long droughts. So that’s why Zinc plants an important role how it absorbs moisture. Zinc deficiencies on some plants will have the Spotting and bleached spots (chlorosis) between the veins first appears on the older leaves first, and then goes on to the immature leaves. It will then start to slowly affect tips of growing points of the plants. When the zinc deficiency happens so suddenly, the spotting can appear to be the same symptoms to that of an iron and manganese, without the seeing the little leaf symptom. Zinc is not mobile in plants so the symptoms will occur mainly in the newer growths. Having a plant that is deficiency in Zinc can cause small crops, short shoots and have a cluster of small distorted leaves near the tips. Between the veins (Interveinal) yellowing is often combined with overall paleness. Pale or grayish, yellowing between the veins; rosetted weak is the signs of a Zinc deficiency. With a low level of zinc in your plants, your yields will be dramatically reduced. Interveinal chlorosis is present in the small, narrow distorted leaves at the ends of really shortened shoots and the shortening between internodes. Leaf margins are often distorted or wrinkled. These nutrients will get locked out due to high pH: Zinc, Iron, and Manganese. These deficiencies will often occur together. Parts affected by a zinc deficiency are young leaves and petioles. Having an excess of Zinc is very rare, but when it does happen it can cause wilting and in worse cases death.



Problems with Zinc being locked out by PH troubles High pH, Low organic matter, High Phosphorus levels in the soil, and or lack of nitrogen.

Soil Zinc gets locked out of soil growing at pH levels of 4.5-4.7, 7.5-9.5 Zinc absorbed best in soil at a pH level of 5.0-7.0 (I wouldn’t recommend having a soil pH of over 7.0 in soil) anything out of the ranges listed will contribute to a Zinc Deficiency.

Hydro and Soil less Mediums Zinc gets locked out of Hydro and Soil less Mediums at pH levels of 5.7-8.5 Zinc is absorbed best in Hydro and Soil less Mediums at pH levels of 4.0-5.5 (I wouldn’t recommend having a pH over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to a Zinc Deficiency.

Solution for Fixing a Zinc Deficiency Any Chemical/Organic nutrients that have potassium in them will fix a Zinc deficiency. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!) And any of the following nutrients will fix a zinc deficiency: Zinc sulfate, zinc chelated, or zinc oxides are adequate fertilizer sources for zinc. Or you can bury galvanized nails in the soil. (Make sure you take off the sharp point at the end to prevent roots from being damaged) Garden Manure, which is slow acting. Greensands, Cottonseed Meal are both medium/slow absorption as well. Now if you added to much chemical nutrients and or organics,( which is hard to burn your plants when using organics) You need to Flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients.

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Iron (Fe) Micro Nutrient and an Immobile element Iron is an important component of the plants enzyme and is also important for the transportation of electrons while photosynthesis is happening... Iron reacts with many of the components of nutrient solutions, which will cause a nutrient lockup to occur, If you add to much Iron without adding enough Phosphorus, you can contribute to a phosphorus deficiency , so watch out how much iron and phosphorus your nutrients have. The Leaves on the plant can turn a pale yellow along the growing shoots, while the veins remain dark green. When you have pH imbalance, it can make iron insoluble. The tissue between the veins becomes pale or white, kind of mimics the magnesium deficiency, but not yellow,

iron has the white where the yellow would be on the magnesium deficiency. The deficiency starts with the lower and middle leaves, while the new leaves become completely lacking in chlorophyll, but with little or no necrotic spots. The chlorotic mottling on new leaves starts first near the bases of the leaflets, so the middle of the leaf appears to have a yellow mark. Iron is difficult for plants to absorb and moves really slowly in the plant. Harder for outdoor plants to absorb when in hot weather. Parts affected by the Iron Deficiency are: Young leaves and Petioles. To much Iron can cause a problem that looks like a PH imbalance, Brown spotting on the top leaves, mainly fan leaves. Can affect the whole plant. Iron Toxicity is rare for Ph below 5.5.



Problems with Iron being locked out by PH troubles

Over watering, pests nematodes, not enough drainage, like not enough perlite. High ph, Soils with low iron, High Phosphorus, Excess Zinc, manganese or copper.

Soil Iron gets locked out of soil growing at ph levels of 2.0-3.5 Iron is absorbed best in soil at a ph level of 4.0-6.5 (I wouldn’t recommend having a soil ph of over 7.0 in soil) anything out of the ranges listed will contribute to an Iron Deficiency.

Hydro and Soil less Mediums Iron gets locked out of Hydro and Soil less Mediums at ph levels of 2.0-3.5 Iron is absorbed best in Hydro and Soil less Mediums at ph levels of 4.0- 6.0 (I wouldn’t recommend having a ph over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to an iron deficiency.

Solution to fixing an Iron deficiency

Any Chemical/Organic nutrients that have potassium in them will fix a Iron deficiency. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!) Foliar feed with chemical fertilizer containing Fe or rusty water can work well. Other supplements that have Iron in them are: Iron chelates, Ferric oxide, Ferrous oxide, Ferrous sulfate, all of these are fast absorption. Greensand, Cottonseed Meal is slow absorption, Garden Manure, which is medium absorption. Manure is most common organic iron source to use.

Now if you added to much chemical nutrients and or organics,( which is hard to burn your plants when using organics) You need to Flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients. Picture 2-3 is a more severe case of iron def

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Sulfur (S) Micro Nutrient and an immobile element Sulfur plays an important role in root growth, chlorophyll supply and plant proteins. Just like iron, Sulfur moves slowly in the plant, hotter temps will make Sulfur harder to absorb like iron. But unlike iron, Sulfur is distributed evenly throughout the plant, mainly the big fan leaves. Sulphur is also a very important element in vegetative growth. First signs of a Sulfur deficiency are pale young leaves. The growth of leaves will remain slow, but the leaves can also get brittle and stay narrower than normal. Can also have small mutated leaves, along with the buds on top of flowering plants will die off. The growth if the plant can be stunted as well as yellowing of the younger leaves and new growth. Unlike a magnesium deficiency where it starts from the leaves tip and around, sulfur starts from the back of the leaves on forward to the middle of the leaves. The Stems become Hard, thin and may be woody. Some of the plants may show orange and red tints rather than yellowing. The stems will increase in length but not in diameter. Leaves will then be stiff and brittle like glass and fall off soon. Parts affected by a Sulfur deficiency are: The whole plant can be affected as well as young leaves, leaf veins. Too much Sulfur will cause your plants to be small along with the size of your leaves, along with your leaves being brown and dead looking at the tips. An excess of sulfur can also look like salt damage, restricted growth and dark color damage.





Problems with Sulfur being locked out by PH troubles Soil Sulfur gets locked out of soil growing at ph levels of 2.0-5.5 Sulfur is absorbed best in soil at a ph level of 6.0- 9.5 (I wouldn’t recommend having a soil ph of over 7.0 in soil) Anything out of the ranges listed will contribute to a Sulfur Deficiency.

Hydro and Soil less Mediums Sulfur gets locked out of Hydro and Soil less Mediums at ph levels of 2.0-5.5 Sulfur is absorbed best in Hydro and Soil less Mediums at ph levels of 6.0- 9.5 (I wouldn’t recommend having a ph over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to a Sulfur deficiency.

Solution to fixing a Sulfur deficiency

Mix 1-2 teaspoons of Epsom salts per gallon of water until condition improves. Any Chemical/Organic nutrients that have Sulfur in them will fix a Sulfur deficiency. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!) Other sulfur nutrient supplements are: Rain water, Ammonium Thiosulfate, which is all fast absorption. Garden Sulfur, Sulfate of Potash, Gypsum. Note: Caution when using gypsum to an already acid soil (pH that is less than 5.5) can have a very bad effect on different types of plants by affecting the absorption of soil aluminum, which is poison to plant roots. Now if you added to much chemical nutrients and or organics, (which is hard to burn your plants when using organics) you need to flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients.

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Manganese (Mn) Micronutrient and Immobile Element Manganese Helps enzymes break down for chlorophyll and photosynthesis production, as well as it works with plant enzymes to reduce nitrates before producing proteins. Having plants that are deficient in manganese can turn the young leaves into spotted (mottled) yellow and or brown areas on young leaves. Dead (Necrotic) yellow spots form on top leaves, while the lower older leaves will or may have gray specks and or spots. Symptoms can include yellowing of leaves while the leaf veins can stay green. Can also produce a chequered effect. As the plant gets newer growths the plant will seem to grow away from the problem, that’s why the younger leaves may be unaffected. On the top of the leaves, brown spots can appear. While the severe areas of the leaves turn brown and wither. Parts Affected by a Manganese deficiency are: Young leaves.

Too much Manganese in the soil will cause an iron deficiency. The blotchy leaf tissue is caused by not enough chlorophyll synthesis. Your plants will seem to have very weak vigor caused by the excessive amount of manganese.



Problems with Manganese being locked out by PH troubles Soil ph of over 6.5, High iron soils, Low nitrogen Soils, Dry weather and compacted soil.

Soil Manganese gets locked out of soil growing at ph levels of 2.0-5.0 Manganese is absorbed best in soil at a ph level of 5.5-6.5 (I wouldn’t recommend having a soil ph of over 7.0 in soil) anything out of the ranges listed will contribute to a Manganese Deficiency.

Hydro and Soil less Mediums Manganese gets locked out of Hydro and Soil less Mediums at ph levels of 2.0-4.5. Manganese is absorbed best in Hydro and Soil less Mediums at ph levels of 5.0-5.6 (I wouldn’t recommend having a ph over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to a manganese deficiency.

Solution to fixing a Manganese deficiency Foliar feed with any chemical fertilizer containing Mn., or mix with water and water your plants with it. Any Chemical/Organic nutrients that have Manganese in them will fix a Manganese deficiency. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!) Other nutrients that have Manganese in them are: Manganese chelate, Manganese carbonate, Manganese chloride, Manganese dioxide, Manganese oxide, Manganese sulfate, which are all fast absorption. Garden Manure, Greenssand are both good sources of manganese and are medium/ slow absorption. Now if you added to much chemical nutrients and or organics,( which is hard to burn your plants when using organics) You need to Flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients.

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Boron (Micronutrient and Immobile element Boron is important when dealing with maturation, pollen germination and seed production. As well as keeping calcium in soluble forms and keeping the stems, stalks, branches strong. Born keeps good color on the leaves and helps produce the plants structure. Boron also aids in cell division and protein formation.

Boron deficiencies will show up first in younger leaves (they may turn yellow), then moves up the plant. Boron deficiency can resemble calcium deficiency. Stunting, discoloration, possible death of the growing tips, bud abortion and development. The Roots will show a stunted with swollen short secondary roots, leaves distorted, sometimes bronzed or scorched. Tip of the shoot dies; stems and petioles are brittle. Boron deficiency plants are easy to tell, because of the spotting the leaves show like a strawberry mark and or splashes of the marking. Boron-deficiency symptoms first appear at the growing points. They also can show signs of newer growths turning gray and or dying, bud deformed, curling of the leaves which are often spotted and discolored. Newer growths appear to look like they are burnt. They can show signs of hollow stems along with yellowish to brownish color leaves. Dead (Necrotic) spots develop between leaf veins, as well as the leaves becoming thick. The leaves will wilt with necrotic and chlorotic spotting. Boron is poorly absorbed with low potassium content. First signs of the deficiency are abnormal growth tips. Having not enough boron can also invite troubles for fungus problems from the internal tissues to rot away, as well as the root hairs along with them being discolored. To avoid having a Boron deficiency try to keep the ph below 7 and to improve the moisture as well as retaining light soils. Too much boron in your plants can produce a lot of problems. The leave tips turn yellow progressing inwards causing the plant to soon die slowly along with leaves dropping a lot. It can show same signs as if a magnesium deficiency, but only happens on newer growths. Parts affected by a boron deficiency are: Growing points and young leaves.



Problems with Boron Being Locked out by PH troubles Soil ph under 5.5 or over 6.8, sandy soil, soil with low organic matter and or lack of nitrogen.

Soil Boron gets locked out of soil growing at ph levels of 2.0-5.0 Boron is absorbed best in soil at a ph level of 5.0-7.0 (I wouldn’t recommend having a soil ph of over 7.0 in soil) Anything out of the ranges listed will contribute to a Boron deficiency.

Hydro and Soil less Mediums Boron gets locked out of Hydro and Soil less Mediums at ph levels of 2.0-5.0 Boron is absorbed best in Hydro and Soil less Mediums at ph levels of 5.0-6.0 (I wouldn’t recommend having a ph over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to a boron deficiency.

Solution to fixing a Boron deficiency

One of the ways you can fix a boron deficiency is to either foliar spray or water regular. Treat with one teaspoon of Boric acid (sold as eyewash) per gallon of water. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!) Other nutrients that have boron in them are: Borax, Boric Acid, Colemanite, Sodium pentaborate, Sodium tetraborate, which are ALL fast absorption. Garden Manure, Bone Meal are both good boron supplements, but are slow/medium absorption. Now if you added to much chemical nutrients and or organics, (which is hard to burn your plants when using organics) you need to flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients.

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Copper (Cu) Copper plays a big role in producing healthy plants, stems, branches and new growths, as well as for the plants reproduction and maturity. It also assists in carbohydrate metabolism and oxygen reduction. Copper deficiency plants shows a lack of growth, growth tips die back, green leaves will show a bluish hue and plants may have a hard time showing maturity in vegging stages. Copper deficient plants causes irregular growth and wilting in the newer growths. The Leaves at top will wilt easily along with bleaching (chlorosis) and necrotic areas in the leaves. Leaves on the top of the plant may show veinal chlorosis.(bleaching of the veins) Growth and yield will be diminished along with spots on the leaves that are necrotic. To much copper in the system will cause the plant to die, as if it was a poison. Near death the plant will induce iron deficiencies and the root system will decay along with abnormal size of the roots, along with little side branching. Some new growths may not open up, along with becoming thin pale green to a bluish hue. Parts affected by copper deficiency are: new shoots, young leaves, and or the whole plant.


Problems with Copper being Locked out by Ph Troubles High ph along with highly compacted soil that has a lack of nitrogen.

Soil Copper gets locked out of soil growing at ph levels of 2.0- 4.5 Copper is absorbed best in soil at a ph level of 5.0-7.5 (I wouldn’t recommend having a soil ph of over 7.0 in soil) anything out of the ranges listed will contribute to a Copper deficiency.

Hydro and Soil less Mediums Copper gets locked out of Hydro and Soil less Mediums at ph levels of 6.5-9.0 Copper is absorbed best in Hydro and Soil less Mediums at ph levels of 2.0-6.0 (I wouldn’t recommend having a ph over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to a copper deficiency.

Solution to fixing a Copper deficiency One way to treat a copper deficiency is by foliar feeding with Copper Sulphate, Cu sulfate, Cu chelates, and those 3 can also be used in soil. Any

Chemical/Organic nutrients that have copper in them will fix a copper deficiency. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!) Other nutrients that have copper in them are: Granular, Garden Manure, Greensand. Now if you added to much chemical nutrients and or organics, (which is hard to burn your plants when using organics) you need to flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients. Damaged leaves will NOT recover. Picture 1 is a copper deficiency, (it may look like a over fertilization ( nitrogen) but look at the bottom of the leaves, notice how they are yellow and a bit of white, also some of the fan leave tips are brown and dying off.)

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Molybdenum (Mo) Molybdenum has proteins that help the plant take nitrogen from the air. A Molybdenum deficiency causes leaves to have a pale, fringed and scorched look, along with weird or retarded leaf growth. Yellowing of middle leaves can occur as well as twisted younger leaves which will eventually die. Molybdenum deficiencies frequently resemble a nitrogen deficiency. A Molybdenum deficiency shows older chlorotic leaves with rolled margins and stunted growth. Looks like a nitrogen deficiency but with the red tips moving inwards to the middle of the leaves. Molybendum deficiency will usually show up in the older to middle aged leaves, then it moves to the young leaves. Generally a molybdenum deficiency occurs when sulfur and phosphorus are deficient. Molybdenum toxicity doesn’t cause to many problems, but may cause problems when the human ingests it. Excessive molybdenum in cannabis will look like iron or copper deficiency. Parts affected are by the molybdenum deficiency are: Older leaves.




Problems with Molybdenum being Locked out by Ph Troubles Soil ph that are under 5.5

Soil Molybdenum gets locked out of soil growing at ph levels of 2.0-6.5 Molybdenum is absorbed best in soil at a ph level of 7.0-9.5 (I wouldn’t recommend having a soil ph of over 7.0 in soil) anything out of the ranges listed will contribute to a Molybdenum deficiency.

Hydro and Soil less Mediums Molybdenum gets locked out of Hydro and Soil less Mediums at ph levels of 2.0-5.5. Molybdenum is absorbed best in Hydro and Soil less Mediums at ph levels of 6.0-8.0 (I wouldn’t recommend having a ph over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to a Molybdenum deficiency.

Solution to fixing a Molybdenum deficiency

One way to fix a Molybdenum deficiency is to foliar spray with Molybdenum, like Miracle Grow All Purpose plant food and Miracle Grow: Tomato Plant Food. These can also be used to mix in with water as well. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!) Other nutrients that have Molybdenum in them are: I think Peters All Purpose Plant food does, as well as Greensand, Lime. Green sand and lime is slow/medium absorption, while Peters All Purpose Plant Food is fast absorption. Now if you added to much chemical nutrients and or organics,( which is hard to burn your plants when using organics) You need to Flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients. Picture 1 and 2 is a Molybdenum deficiency in late flowering

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Feel free to add more pics and info.

[Romeu9]

excelent!

[cateros]

I always wonder if your growing in promix bx do you shoot for a ph of 6.5 or would a ph closer to 6.0-6.2 be more appropriate for the medium? I only ask as 6.2 ph is the standard ph of promix after 7 days of water saturation it will stabalize so just wondering if for the future would you add dolomite to promix if you leave it as is or if only if you cut it down with perlite to allow for better drainage the excess perlite will lower the overal CEC of the medium .

[Syn]

Very nice thread !

[dHetep]

cateros I grow starting with a 1 inch rockwool cube the transfer to clay grow rocks I wouldn't be the person for this question. However super blue blaze, fuzzy or samuelo may be able to answer that question

[berrystraw]

does anybody know what it could be?

it looks like if you rubber a pencil on a paper, silver,

it involved only a few small leaves inside

 I flushed the plant

today is touching the big leaves outside

on the lower part of the plant

 

it is only on one plant out of three

 

I found a fungus gnats as a possible reason

in fact I have 80% humidity cause outside in always raining

[Dust]

yes it looks like a virus or a fungus maybe which one is another thing, some deficiency look a little bit like htis, but it doesnt shine like paper pencil like yours normally.  The Manganese deficiency can turn up like this a little bit, check some info about it and see if it corespond to your symptoms.

 

Good luck!