Auto flowering: Yellow/brown spotting

Hey guys! New to the forum and to growing.
I started to notice yellow/brown spotting on the bottom leaves after the new leaves grew in and it started to flower. It’s been hot here and getting full sun. Admittedly I’ve been watering too much but the spotting looks like something else might be the issue. I thought it was a calcium deficiency and started using “Cal-mag.”

I’ve been reading some posts and I learned I already messed up by using Miracle-Gro potting soil and their fertilizer (weeks ago) but it’s been looking good until the spotting started like I mentioned before. Any tips would be much appreciated!

A few things, take the pot out of the pot.
Are you in miracle gro soil?
Miracle gro nutrients are not oriented towards cannabis, but they will work. Just not the best.

Calcium could be locked out if you haven’t checked the ph in your soil. Miracle gro soil is always causing ph issues for cannabis.


Yes it is miracle gro potting soil and unfortunately all I have at the moment.

If I take it out of the pot what would you recommend I put it in?

I don’t have ph tests handy either but if the ph is preventing calcium absorption how would I fix that?

Are you thinking it’s more likely a ph issue than an overwatering/dampness issue like algae/fungus?

There’s a little of that, if it’s that wet often.

Yes, just cover the with additional soil.

You’ll need to lower you ph with ph down, or phosphoric acid. There’s a few different ingredients that do the same thing.
You kind of have to have a baseline before adjusting.

Is this one have a label like “feeds for 6 months”?
That one typically has time release fertilizer in it.

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Yes that’s the one. “Feeds 6 months” and has the little balls in it.

What do I need to cover with additional soil? “Yes, just cover the with additional soil” ?

This is probably a dumb question but there is “organic fulvic acid” in the Cal-mag supplement I’ve been using wouldn’t that lower the ph too?

Yes it could, and the soil that feeds for 6 months is part of the issue. You’re over watering and every time you water it releases more nutrients.
I still recommend to transplant it.

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Got it. Ok so I’ll stick just to water for a while and let it dry out more in between waterings. I’ll probably take your advice and transplant it to a 5 gallon mesh bag.
Thank you so much for all the advice!

Transplanted in non-Micracle-Gro soil but now tips of newer leaves are browning. Not sure what to do except wait and hope for an improvement.

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Brown tips of the affected leaves have begun turning yellow.
Yellow spots on the older lower leaves have turned white.
Signs of some yellow spotting beginning to form on the edge of the new/broader leaves.
However it is noticibly taller and the buds seem more developed with even more white thistles.
Not sure if this is good or bad progress. Still only giving water when the soil is dry to try to fix the nutrient burn/overwatering issue I caused.

She’s probably hungry, and she’s flowering.

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What should I feed her?
I’m kinda worried to give her more nutrients since I already went overboard with the 6 month feeding miracle grow and Cal-mag.

Look for fox farms bloom nutrients. They are available in hardware stores. Not sure of your area.

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Thanks! No worries, I can always order it in of I can’t find it locally. Would you recommend Fox Farm Tiger Bloom or the Big Bloom?

You can buy and use both.

Here is the Fox Farms feeding schedule. I do not use these nutes so can’t be too specific.


Thank you so much! I just ordered both yesterday. They should be here in a few days just in time to water it again. Still paranoid about overwatering it again.

Yesterday I gave my autoflower a combination of Fox Farms nutrients (Big Bloom, Grow Big, and Tiger Bloom) in the amounts recommended on the above chart for 12 hrs of sunlight. Fingers crossed there is a noticeable improvement.

It has not gotten worse since last posted but I’m still concerned about the discoloration on the leaves. Here’s just the most recent pictures.

The newest growth looks good. Let’s see what happens and how she reacts.

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Maybe you should flush out the nutrients that you already feeding your plants. If you are going to switch to fox farm. Nutrient burn is what I know. Burned my plants with miracle grow outside while using organic fertilizer.

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Believe me I’m worried about that too!! I transplanted into better soil and flushed a few times already with just plain water since the last time I ever gave nutrients so I’m hoping burn won’t happen. I’m keeping an eye on it though. I haven’t noticed any changes yet good or bad so fingers crossed! Thanks for the input guys!

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It sounds like you’re doing all you can

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