15" in 3.5 months that's on the slow side, you need to watch some u-tube video on growing or read some books You can get 15" in 1 month Research it'll save you time and money
Never, unless u up the light. U must have a really weak light source on it. If that is a reg 60 watt light bulb it is not even putting out 1000 lumen. If nothing else put the light with in 2" of the plant if u want better, but still slim chance of getting any results.yeah i knw im slow so how long do u think it will take me to get some results