Hydroponics Growing plants in nutrient solutions without soil. Leaf Curl Leaf is showing stress. This can be caused by any number of things, over watering, overfeeding, even insect or fungus damage. A mother plant may be grown from seed or clone. Mold Humidity to high.
Humidity is moisture.
Here in Holland we have a lot of water and a lot of rain. All these things cause this S word. Spring time - wet rainy April days. A scale from 1 - 14 that measures growing mediums acid to alkaline balance. Cannabis grows best in a 6.5 to 8 pH range.