Rockwool
Well-Known Member
Okay so basically yesterday I noticed some grey streakage on middle to upper leaves which I assumed was Phosphorous deficiency due to not watering in about a day and a half. I am growing in Rockwool cubes and having done research have found that under watering can cause a spike in pH. I assumed that due to this it had caused a deficiency in the plant. Anyway, this morning I noticed that these grey streaks have now turned purple and I am unaware of what this means. Firstly I am always in pH of 5.8-6.4. GH nutes. adapted Lucas' formula (not really L's formula anymore but) 3 ml grow 8 ml Micro and 14ml bloom for every 3.4l. EC is always at 2.0 meaning ppm's are roughly 1000-1100. My water before hand has an EC of 0.05. I water typically twice a day but recently decided to let plants dry out a bit more. This plant in particular was bone bone dry, and I have now fed it after noticing what i assumed as a P def, but have now noticed progression into purple streaks. 400w light above this plant and the plant is approx 3 feet. Temp is 80f in day and as low as 50 at night. The purple stems are also signs of P def right? But could this also be caused by cold temps at night? Anyway.. enough jabber, pics. 3rd week into flowering.