Manganese Deficiency Help

COM Stonington Blend, 7 gallon bag, WW photo, HST then SCROG. 18th day of flower, stretching very nicely. Showing signs of manganese deficiency. Using all COM nutes and additives per schedule. What can I use for manganese problem?

Manganese is pretty rare. Likely something else. How about filling out a Support Ticket and attaching photos of the plant?

COPY/PASTE the below list into your forum post.

Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so; Or post
NA (non applicable)

-What strain, Seed bank, or bag seed (photo or auto)
-Age of plant
-Method: Soil w/salt, Organic soil, Hydroponics, Aquaponics, KNF
-Vessels: Type and capacity of container (fabric, plastic, etc)
-PH and TDS of Water, Solution, runoff (if Applicable)
-PPM/TDS or EC of nutrient solution if applicable
-Method used to measure PH and TDS
-Indoor or Outdoor if indoor, size of grow space
-Light system List brand and wattage/spectrum
-Actual wattage draw of lights
-Current Light Schedule
-Temps; Day, Night
-Humidity; Day, Night
-Ventilation system; Yes, No, Size
-AC, Humidifier, De-humidifier,
-Co2; Yes, No

If growing Hydro some additional questions:

-DWC? RDWC? Autopots? Ebb and Flow? Other?
-Distance of liquid below net pot (DWC)
-Temperature of reservoir
-TDS of nutrient solution
-Amount of air to solution

Always try to upload a clear picture in white light of any issues you may have to allow the community to assist you.

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ILGM White Widow fem photo
Sprouted 7/16
HST into semi-circle
Flipped 10/1
Organic soil COM Stonington Blend
7 gallon fabric
H2O pH 6.0, well water
HACH Pocket pH meter, calibration check each day
Indoor in developed basement
4x4x6.6, half of a 4x8x6.6
SonoFarm SF4000, full spectrum, 350 watts
12/12 lights
Day 71 degrees/40% RH
Night 67 degrees/37% RH
8" Vent system, no filter - vented outdoors
AC and heat in lung room
55 qt. dehumidifier when needed
No humidifier att

Epsom salt or magnesium sulfate


How much per gallon or top dress?

Soil is looking N depleted as well: top-dress worm castings to stay organic. I second the Epsom Salt.


Never used Epsom. How much do I use?

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@sandune I use it at 1 teaspoon / gal water







Thanks everyone, it’s lights out now so I’ll get to it tomorrow. I’ll post pics and notes on the results. Thanks again!


I’m currently growing in COM Stonenington Blend for the first time. Growing autos as well. Previously used Fox Farm OF didn’t have to feed first 4-6 weeks. Was expecting similar results but haven’t. Had to start feeding from the first week. They have done well since. Tons of fungus gnats easily controlled with neem oil and decreased humidity but a pain in the butt.

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The fact there are holes worry me, look under your leaves for pests. 1 tsp is a Lil much I’ve found my organic girls love 1/2 tsp once a week but I also feed them a dose of nectar of the gods

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Sorry I add mine using a scale @ 1.18 grams / gal

I have found no pests on the plants except gnats. I look 4x weekly with magnifier glass.