HELP! Leaves are getting brown spots, starting from the center of leaf

[jmeredi2]

Hi, first time grower here. My plants are in a green house, which is supplemented with 1000W of LED light for when the sun has gone down (they’re getting about a 18/6 light cycle). They are 2-3 weeks old and growing in Fox Farms Ocean Forest potting soil. The PH is at 7 and I’m watering about once every 3 days - or once the soil is dry at an inch deep. Temperature is set at 75 degrees and humidity is at 70%.

The brown coloring generally occurs on the lower leaves, but I can see traces of it on the upper leaves as well.

 

[Canuck147]

Nutrient lock-out. Get your pH down to around 6.0.

 

[s62]

Does lock out occur in soil at a ph of 7? Water or soil ph? I’m confused. Kind Soil calls for a waster ph between 6.3 - 7. I know nothing about soil pH because I’ve never had to measure or monitor it.

 

[Canuck147]

Not talking about soil - pH of the water you put in the soil should be between 5.5 - 6.5.

 

[s62]

Got ya! Thanks for clarifying.

 

[Canuck147]

I've never measured my soil nor my runoff - just what's going in.

 

[Toker1]

Ph is too high. Fox farm recommends 6.3-6.8 for ocean forest. Looks like you are experiencing a phosphorous deficiency.
Flush with plain water adjusted to 6.3 until the run off water is somewhere closer to the lower spec.

 

[jmeredi2]

Thanks! I'll try lowering the pH of the water.