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Strange Leaf Discoloration?

Hi Folks,

Can someone take a look at this and tell me if you know what it is? These plants are planted in the ground with a potting soil mix. I recently added a top dressing of steer manure. We are also blooming the plants we light dep. This is the second week. The discolorations starts on the inner and bottom leaves.

We are testing the soil to see what the nutrient levels are and spraying the leaves with Azamax but I am unsure what is causing it. There are no apparent bugs on the leaves using my 100x usb microscope.

Thanks is advance!



Quick question – is that black material inside the leaf, or on top of it? Might tell us whether it’s a parasite of some sort, or some kind of nutrition/environmental issue.


Hunter, I believe it is on the inside. it doesn’t rub off




I would guess this is definitely nutrient uptake/lockout, pH ,related I welcome you to a free shipment of our product to treat your entire farm with…as we have a long history of fixing these kind of issues I will post more when I get to my computer.




I would guess…not exactly sure on what it is…sorry

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I had similar issues when mixing mushroom compost and soil in a 1 gallon pot. Did a few plants just to see what I could learn and…plants definitely locked up. Had samples of the compost tested and turns out the EC was over 5.0, whoops. Maybe your steer manure is similar?

When did you first notice the issue? Are all the plants that have manure top dressing showing the same signs of stress?

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I was definitely thinking of the manure comment. Cellis, I stated this before… We frequently describe URB as a product which builds the soil health so that anything with a root responds favorably. We used to say that we increase nutrients – -- however, it is more appropriate to say we balance the soil.

We had an organic farmer who had been using chicken litter for over 20 years…his P was off the charts too high; all manures are high in P, but especially chicken litter. In his case, URB caused a reduction in P which was required to balance the soil. I am guessing there may be too much P in this case.

High Ph soil tends to go lower with URB and low pH soil tends to rise.

I am not sure what is going on with your plants, it may be a pH problem, may be lockout, it may be fungal… What I do know is It may prove beneficial for you to give us a shot :slight_smile: No risk involved.

URB is essentially concentrated “Mother Nature” —a liquid formula of several carefully selected micro-organisms blended in a humic acid carrier. Starting from a list of 200 beneficial soil bacteria strains, the candidates were narrowed down to the most compatible and complimentary microorganisms to perform specific beneficial functions in several different areas related to plant health and vitality; 6 bacteria, 1 fungi.

URB has demonstrated the ability to significantly increase crop yields while simultaneously decreasing fertilizer usage. URB products also reduce water and pesticide usage.The result is a significant increase in profits for customers in a wide range of applications and growing mediums. Additional benefits for Cannabis grown with URB are higher nutrient content, translating to higher cannabinoid percentages, faster and earlier germination rates, earlier maturation, and better ability to withstand environmental stress such as wind, extreme temperatures, and drought. All these benefits are accomplished without reliance on growth hormones, genetically modified organisms, or synthetic chemicals of any kind. URB’s proprietary microbial formula is organic, sustainable, and environmentally friendly. It is designed to work on many different crops in a wide variety of growing conditions.

URB rehabilitates soil, making it healthier and better able to hold water, nutrients and oxygen. It is highly compatible with organic farming and also has great results when used on conventionally cultivated land. URB was developed at Michigan State University (MSU) over a six year period. Research included extensive greenhouse testing, over 200 outdoor test plots, and multiple commercial user field trials operating under real world growing conditions.

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Calcium deficiency! Check pH of soil? You can apply pelletized gypsum or lime depending on your soil pH. If bellow 7 more lime than gypsum. Above 7 more gypsum than lime


I was thinking cal/mag from botanicare. Your solution is better ethan, I still feel our solution is best. Of course what company wouldn’t say that…but if you are having soil issues, let us remediate it for you. You don’t even have to measure your pH. :smiley: Just dump some URB in that soil!!!


Here is a study summary about that farmer using chicken litter in Mississippi Mississippi_phosphorusReduction_summary.pdf (350.7 KB)

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annnd because your plants are in the earth, you may want to take a look at these as well…

Illinois_waterNitrate_summary.pdf (1.1 MB)
MDC_one_page.pdf (290.8 KB)

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Here is a testimony to what I am saying about not having to adjust your pH with URB.


"Our Gerber daisies we grew last year (our 1st season using SumaGrow)…was a nice crop and we were late planting and over produced…This year we reduced the quantities a little, planted on time, and have sold 95 percent of them and they are the best looking Gerbers ever with a higher percentage of the plants producing 5–8 flowers per flush of flowers and the few that stayed here beyond the 1st flowering seem to produce following flush of flowers quicker.

The greenhouse production areas are still using far less water than usual, I can only guess at 40 percent less, it might be more. As plants reach mature size, they use closer to what is expected, but still a guess of 10 percent less. Mature flowering HB in some varieties use 75 percent less. This also has saved us 60 percent of our normal fertilizer on those plants…

Our petunias that always show Fe & N deficiencies even with using foliar Fe & N have always required multiple drenches to lower the pH if they stayed longer than 6 weeks due to our bicarbonates in the water. Last year they did not need any pH adjustment to help them pick up nutrients after we started SG…We have not had to adjust the pH at all this year.

We still apply foliar Fe as always on petunias & N as we do on all our crops & we have had to reapply slow release fertilizers to keep them longer as usual except that we are using 20 percent lower rates getting equal results in most varieties. When it got warm in mid March we drenched again with SG + KNO3 4 oz/100g, + a soil surfactant Soaker, the next day our hand watering was reduced and we are still using less hand watering than usual even though days are longer, temps are up a little…”

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Leaves make poor roots. :innocent:

Oy! I know hard water. The bane of a midwestern grower! We resorted to phosphoric acid. Had to adjust the rest of our feed to account for 120 ppm of phosphorus from the phosphoric acid. That was just to get us to a pH of seven with minimal residual buffering.

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How does it work with septic field recovery?

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It’s funny you mention that…not sure as to septic field recovery but I am sure there is a formulation in the archives for that… Do you have a need? I can get you an answer.

Our principals have cultivating microbes for 20 years, first under the name Bio Solutions Franchise Corp. Bio Solutions remediated waste from restaurant grease traps, boasting 42 service locations at its height, ranging from fast food restaurants to some of the swankiest restaurants in the country.

When Hurricane Katrina hit, it took the factory’s roof with it. By the time the factory was operational again, Bio Solutions had lost several customers. Those lost accounts lost combined with accounts they had lost while pushing clients to move from remediation to recycling forced them to rethink their company. Bio Soil Enhancers was born and then that morphed into SumaGrow, which I found when reading Popular Science back in 2009. I reached out, wanting to invest, and also wanted to try it on my MMJ crops…that relationship blossomed and now we have a formulation and company called URB Sciences which is our formulation for the Cannabis plant. Next venture after this, is our “home gardener”, lawn and garden formula, this is why we have the founder and creator of EcoSmart on our board to access the 25,000 retail stores his product is in, assisting us to take our technology to that market. We also have john greenberg of to help us along the way on the more “main stream” side of the house.

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We have a septic system in northern Minnesota! How could we not expect problems.

No things are running smoothly pump the tank annually and don’t let lint into the system. Big problem with plugging of the pore spaces in lateral fields with small particles. Only approved solution by the state is cold fracture of the field or new field. Ounce of prevention.

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we don’t use soil, eliminating all soil born problems.


Well that is definitley one way to handle it. Nice tomatoes. Legalize tomatoes! …as I once saw on a shirt somewhere :wink:

I see that you offer some nice state of the art Ebb and Flow systems. Even in those brother, I welcome you to give us a shot. Check out this post to read about a reputable organization utilizing a similar system showing results hydroponically after 4 short weeks in flower. He has 6 100 gallon tanks feeding each tray of about 24 plants. A small 1200 sq. ft grow under LED’s and in recycled glass. 3rd Party Results

Maybe we could work something out and include a grow cycle’s worth of URB in your packages.


That’s from Growers House :slight_smile: