Braune Flecken auf Blätter

Ph and or cal mag Problem: Calcium is an important nutrient that helps provide structure to the cannabis plant and helps it withstand stress like heat. When your cannabis plant has a calcium deficiency, the main symptom that you’ll be able to notice is brown or bronze splotches or spots on your leaves. It is also often associated with yellowing (though leaves don’t always turn yellow). Occasionally the splotches may appear purple especially under LEDs. Calcium deficiencies are often caused from low pH at the roots, but also occasionally from growing in soft/filtered water