Advice Needed -- Yellow splotches on leaves

Auto Berry Ryder, 2 weeks old, 400W HPS, 30-35% RH, FFoF, water every 2-3 days , Brita filtered tap water

Seeing yellow splotches on leaves... started a couple days ago.

I have two plants that are using same soils, water, etc. but this plant seems to have way more yellow blotches on the leaves

you can also see the leaf edges curling upward on a couple leaves ...

your leaves will get dead spots in them from bugs. Look for any bugs under your leaves. or from a calcium deficiency. If you don't see any bugs it's probably the deficiency.
Your leaf edges will curl up from heat or from a Phosphorus deficiency. Your other leaves look good. I'd say it's a Deficiency.
Cal/Mag, and she looks like she wants more phosphorus. Nitrogen looks good, you don't need to increase that.
Young plant fairly new soil you shouldn't be having problems with pH yet.

Don't water on a schedule. Only water when the plant needs it. You can get into a over watering condition very easily.

Good Luck with You Grow.

Thanks. What would be the best/cheapest way to introduce cal/mag/phosphorous to the plant?

The cheapest way to introduce cal/mag to your plants is to keep your ph in the correct range. The soil is loaded with cal/mag...and proper npk and plenty of micro nutrients. Like he stated previously, don't overwater.

NooooOooOooo! The problem seems to be getting worse. Now leaves on both plants are showing the yellow specks.

I've checked under a couple leaves and I see no pests whatsoever. I ordered a 30x + 60x magnifying glass off eBay that I should have by Friday.

Regarding pH... I have no idea why my pH would be off. I'm using Brita filtered tap water... which I would assume to be fairly normal pH-wise.

Unfortunately, the soil pH meter I have doesn't seem to be working well. I was getting a reading of 6.9, but I'm not sure if it's just broken.

Anyone know where to get some pH water testers on the cheap at like walmart or something? I'm assuming if I can at least measure my water used for watering, the pH of the soil should match?

Can't lose these plants! This is my first grow!

a lot of time the fox farms shows ph problems after about a month esp. if overwatered. There are oyster shells used as a pH buffer and if you water too much, it loses the buffer and the pH drops because of all the nutes in there.
Next round if i were you, running ffof, add some lime and perlite in there.

the dirt is going to have a different pH than the water. it mixes together. You might try unfiltered water from a hose instead of the charcoal filtered brita water. It is probably filtering out minerals the plants could use. I got my 4 in 1 tester at a nursery for 7 bucks (light meter, pH, moisture, etc.) find a technique that works then you can lose the tester and its OK

Start watering with distilled water until you can find a good way to check your ph. Distilled water is usually slightly acidic and just right for plants in soil. The best way to check your ph is with a good electronic meter like a Hanna brand meter. Many other testing methods are not accurate..the drops, the pill, test strips..these can all be misleading and will ultimately make things worse. I am willing to bet your tap water is well above a ph of 7. Also the britta filter you are using is not removing chlorine or chloramine, both of which are destroying your beneficial bacteria and fungi that are working in your soil. Good luck

Hey man,

Don't worry about those leaves. They were your first set of true leaves right? If so they will die and fall off eventually anyways. It may be slightly premature on your plant but there could be hundreds of reasons for that, all of them inconsequential at this point. It may be from pests but I seriously doubt it this early in your grow. Brush the top and under side of the leaves with tap water if you want to be sure you are rid of any pests. Most importantly, DO NOT DO ANYTHING DRASTIC. Cannabis plants are resiliant and will fix most problems on their own in a couple days. The worst thing to do is to get uppity and start messing with chemicals and pesticides on a plant this small. Cal mag is great but is only needed with R/O water or distilled. There are plents of minerals in tap, if that is what you are using.
The leaf curling is usually due to temperature. If the temps is close to 80 or more, plants will do this. Ive also had plants that seem to do this through genetics as well. If your lights are really close, back them up for a day and see if it gets better. If not then monitor plant for additional symptoms.
Believe me, if your plant is in serious trouble, it will be much more obvious than it is now. Purple splotches, purple stripes, completely yellow leaves, necrotic patches, and drooping leaves are what need immediate attention.
So, try backing up the lights, rub the leaves down with water, and don't mess with unneeded nutes. If the problem continues it will be infinitely easier to diagnose with additional symptoms.


oh.... check your humidity, humidity problems disguise themselves as nutrient problems. Min- max range: 40%-65%. Ideal range 50%-60%.

Thanks all!

Dgringo69 said:

Start watering with distilled water until you can find a good way to check your ph. Distilled water is usually slightly acidic and just right for plants in soil. The best way to check your ph is with a good electronic meter like a Hanna brand meter. Many other testing methods are not accurate..the drops, the pill, test strips..these can all be misleading and will ultimately make things worse. I am willing to bet your tap water is well above a ph of 7. Also the britta filter you are using is not removing chlorine or chloramine, both of which are destroying your beneficial bacteria and fungi that are working in your soil. Good luck

Click to expand...

Interesting. I remember reading that Brita filters do indeed remove chlorine and supposedly chloramine as well...

So this earlier this morning, I had watered each plant with 8 oz of water. I will let them dry out for a few days and monitor the conditions. I will likely only use distilled water for the next batch of watering.

I have been misting the leaves 2x daily. I wonder if this could be contributing to the issues? I will also lay off on misting the plants for a few days.

homegrown36... I do have low humidity (30-35%) since i live in the desert. won't have a humidifier for a week or two I'm afraid.

Just one more note. Use tap water not distilled unless you have a water softener. Tap has the trace minerals needed without expensive supplements. Plus, water adapts to soil ph not the other way around. Use dolomite lime powder to buffer soil to 7. Ive had plenty of ph issues wil FFOF and dolomite lime will correct them within a week and a half.

Misting leaves will burn the tops. Could be your spotting issue. Foliar feeds are not neede unless there are deficiencies present.

No worries about the humidity for now. They will present as deficiencies and may hinder growth slightly but relative humidity will increase with more transipiration as your plants get larger. Just be mindful not do mis-diagnose small issues that could be due to humidity problems (namely crispy leaves and small "burns"). With that said, a small humidifier in front of your fan goes a long ways to a grow.