Changes in the leaves. 8 week old GG Autos - problem or no?

Gorilla Glue Autos

8 Weeks old

We are getting some changes to the leaves. A week ago after I had fed them nutrients, fox farms, the next day I noticed what looked to be nutrient burn from my research. The tips of the leaves were turning brown. Same as I have been feeding them since I started about 5 weeks after planting because they are in Fox Farms Ocean Forest.

I went 5 days without adding any nutrients in the water. I did feed them some yesterday, less than usual though.

Some of the leaves are yellowing mainly on 2 plants, and there are some dark spots on some of the leaves. We noticed yellow leaves before and why I started the fox farm trio.

I have checked the PH of some run off a couple of weeks ago and read 6.7 I believe, but I am not real confident on the process of reading the PH. We have been watering with jugs of spring water the whole time.

The question is, is this normal at this stage or does it look like we have an issue?

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Normal to a degree but yours look hungry. I would feed cal mag. I’m growing gg4 photo and it was the first and only plant to yellow off out of 4.

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It is funny how they can change overnight! I just ordered some cal mag since it doesn’t look like I can get any local. I do think they may need more nutes but afraid now to feed them too much.

Thanks guys for the feedback.

I’m at the end of flower with my gg4 and it’s dropping about 25 leaves a day. The change from dark green to light green was swift and unavoidable imo didn’t matter how much nitrogen. Then they turned yellow and wilted off a week later.

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I would advise to look into manganese and phosphorus deficiency…

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Thanks for all the feedback. I’ll have some cal-mag tomorrow. I fed them a little this morning.

Another question: would it be OK at this point to defoliate some more? I did a little mainly on the lower part of the really bushy 2 about a week ago. Don’t know if defoliating more at this point would be harmful.

Definitely agree with needing to feed. The FF soils will give you several weeks; still need the cal-mag.

For soil, you should be closer to 6.5 for optimum uptake across the board.

There is some flexibility in the range; however, you can see that at below 6.5 you risk losing the uptake of Ca and Mg, very important for the plant.

Best of luck.


@PP3121 thanks for the input!

What do you suggest is the best way to actually test the PH? Water the plant until water runs out of the bag and test that with a PH meter? Some sort of soil tester? I can’t seem to find a clear answer on that.

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I have not done it, but several people here have referred to what is called a “slurry test” to test soil pH. It involves putting a small sample of your soil into a container and adding 7.0 pH water to it to test the soil’s pH.


To get a ph reading water till runoff. Collect some of the runoff and test it with a ph meter. Also how I measure ppm to see if plant needs food. If you don’t already have one get a ph meter and ppm meter. Like @PP3121 said your ph should be between 6.5-6.8.

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You got some sound help already. You should take the pH of water going in to ensure you are at the correct reading. Then take the ppm and pH after watering and compare readings.

Make adjustment accordingly.

As @Oheeeoh stated, only way to know the pH of your soil is to do the slurry test.