this is my first grow. I planted these 20 days ago from some seeds in my weed so, I guess they’re Photoperiods? I noticed these brown spots on the leaves about 3 days ago and I’m not sure what it is. I’m using organic potting soil mixed with some worm castings. I’ve used one application of the FoxFarm Grow Big Liquid Plant Food 6-4-4 6 days ago and before that I gave them a little bit of organic fertilizer I used from soaking potato skins in water, about half a cup. I’ve read it could be a fungus and that Neem Oil could help so, I sprayed them with a small diluted application of it. Also read it could be calcium or magnesium deficiency. Looking for any help. Thanks
Could be several things, might be as simple as just splash back damage from water/feeding, the new growth looks ok but its hard for me to tell from these pics. Those lights will not be enough. Do you have any drainage on those totes? What ph are you running? Have you checked your runoff ph and ppms yet? Might be locking out nutrients
Here’s some closer pics with different lighting of the plant that’s turning colors. I drilled holes in the bottom of the totes for drainage. I’ve never tested the runoff. The PH of the soil was sitting between 6.5-6.8 but then it jumped to 7. I used soil acidifier on it yesterday along with a watering but I haven’t noticed any changes yet. I’m not even sure these PH readers even work
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I wouldn’t worry about the bottom leaves. It is normal for them to degrade. It just looks like they’ve been splashed with water. If you are feeding Grow Big you also need to be feeding Big Bloom. It contains the micronutrients your plant needs. You will eventually need Tiger Bloom as well.
You are going to want to get those in pots with drainage. Cannabis does not do well in wet soil. Cannabis tolerates dry soil far better than wet soil. Let your soil dry out btw waterings.
Welcome to the forum.
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Yea i started out with one of those stick in meters as well, not great and ended up in the trash pretty quickly. Your new growth looks good so either just splashed them or they were touching the soil, or you solved the issue. Keep an eye on new growth to see if it keeps spreading. Those damaged leaves wont repair
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The pronged meters are inaccurate and cannot be calibrated. pH meters tend to drift over time. Bluelab and Apera both make good meters. I suggest getting one that measures PPM as well. I have an Apera PC60 and it is very accurate and it works fantastic.
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My plants had the exact same thing happen, i thought it was water splash too but the two bottom leaves eventually turned yellow and have pretty much withered now, however the one on the second row is actually starting to recover after a transplant, it will always have its brown spots but the yellow is turning green again. I cant offer an explanation but i will say your problem was identical to mine and mine are bout 2 and a half weeks older than yours and growing no problem.
Careful on all the nutes tho maybe, ive just been giving mine water up until next feed