Brown spots, yellowing bottom leaves

majiktoker recommend for me to use it in my soil that’s the only reason I said that

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I was told that silica was for hydro and rock wool , and I think coco. But soil has enough in it naturally. I think @Majiktoker was the one who told me this , but I maybe wrong.

There maybe Extreme situations that may call for it , and @Majiktoker would be the guy to turn to in that case.

There are other soilless mediums that are not hydro so that may be it as well i.e. Promix

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@Fever @eric2 @Wishingilivedina420state

All soils contain silica plants will use all of this by type end of their cycle also depending on the silica your adding yes than can cause other problems.

I recommend rhino skin if your looking for a potassium silicate because of lots of reasons, and it has been Proven that plants with silica are healthier than plants with out.

@Wishingilivedina420state you had other problems because one thing to consider, when adding silica (rhino skin) for example it is a pure for of potassium silicate and is absorbed by the plant in 24 hours. The reason likely for other problems is using a silica product in soil it increases the uptake of other elements taking that into a factor when using silica in soil you need to increase you feedings or you can certainly look forward to different deficiencies.

It also helps with numbers of other things.

FYI im a soil grower not a hydro grower and i dont use soilless mixs


Thanks @Majiktoker I thought you help clear that up for us.


My pleasure

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Leaf septoria or yellow leaf spot is caused by Septoria cannabis and S. neocannabina, both of which are fungal pathogens, targeting cannabis in particular. It occurs on outdoor grown marijuana, triggered by warm weather and rain. It can also appear in plants lacking sufficient nitrogen. Yellow leaf spot will first appear on the lower leaves of the marijuana plant. The spots can range in color from white to grayish brown to yellow, first appearing as small round lesions. As yellow leaf spot matures, it takes on a pimple-like appearance, expanding in size.

Yellow leaf spot will damage the leaves and sometimes the stems of your cannabis plants, but will not kill the crop. However, if left untreated it will reduce yield. Infected leaves dry at the site of the spot, eventually crumbling and creating a hole where the spot began. Heavily infected leaves will turn completely yellow, dry up and drop off. If the fallen leaves are not removed, you have just created a landing ground for spores to overwinter. This means they lay low until warmer weather arrives which is when they do their damage. Yellow leaf spot spores rely on the wind, water and hitchhiking onto passersby for their travels.

Yellow leaf spot can be prevented from attacking your cannabis garden through crop rotation. This means choosing a different planting site after each harvest. If this is not possible, then once you have harvested a marijuana crop completely remove any evidence of the previous vegetation and till the soil well, removing all debris. Prepare the site with sterilized compost and work into the soil. This should provide enough nitrogen to give the new crop a healthy starting ground. In the event you have no available compost (every gardener should get into the habit of creating a compost pile) then add blood meal, fish meal or soybean meal to the existing dirt. This will provide the nitrogen needed for your cannabis. Be sure to sterilize all gardening tools with peroxide or rubbing alcohol before storing.

Another option when starting a new marijuana bed is to apply a fungicide to the planting site before adding seed or seedlings. There are various natural solutions you can either make yourself, or buy already mixed. Adding beneficial bacteria, such as Bacillus Pumilis or beneficial fungi such as Trichoderma will benefit the soil if you have no compost to incorporate. You can also spray the area with essential oil mixtures containing cinnamon, clove, coriander, neem, or sesame. Spraying the soil with compost tea or a baking soda solution can help to prevent yellow leaf spot spores from settling in the area.

Water your cannabis plants in the early morning or early evening. Water the soil, not the leaves. In so doing, the sun’s rays won’t burn the leaves. This practice should be adhered to no matter what you are growing.

In between harvests, if yellow leaf spots find your marijuana patch, the fungus can be controlled in several ways:

Physically remove all affected leaves and destroy them.  Do not add any diseased plant material to the compost pile.
Spray the affected areas with a mild solution of ½ teaspoon baking soda per gallon of water.  Do this in the early morning or in the evening so the leaves dry before the sun heats the day.
Apply a Bordeaux mixture to discourage the disease from spreading.
Spray the plants with a neem oil solution in the early morning or evening to avoid the sun burning the plant leaves.
Use something like Marijuana Booster to avoid nitrogen deficiencies.

Will joint


@garrigan62 once again you have posted more info at one time than I can find on a particular subject. Have you been talking to bob …I hope they pay you for this.if ilgm should.

Thanks for all the info guys.

I tested the soil and it was pretty low, 6.5 on top, 5.8 on bottom and runoff. I added some calcium and mag, just a 1/3 dose, and also gave it a good flush. I raised the ph but now it’s about 6.8-6.9 on top and around 6.3 on the bottom. We’ll see what happens and I’ll post results in any case someone else has the problem.

I noticed another leaf with the brown dots. There are two and they mirror each other on the leaf, similar to pic #3. This leaf is also close to pic 3 leaf (same side, same height, same distance to light). It is ocuring 2/3 from the base of the leaf (1/3 from tip of leaf).