Right so the leaves on all 3 of my plants (all different species) are turning bright yellow. Like the whole leaves. It started at the bottom just after switching to 12/12 and I've just left them for 4 days while at a festival and now only the top of the colas are still green. I watered them before leaving so I don't think it is underwatering. Why could this be? In feeding them the correct amount of nutrients every 3 feeds I give them...
Pictures and information about your grow, medium, lights, nutes, environment, etc. is required to make any type of determination.
I'm not a soil grower but it looks like a bad nitrogen deficiency, especially the one pic with your hand holding the leaf - that looks like classic nitrogen deficiency. However It's hard to tell the amount of yellow in the leaves with a yellow light shining on it - a picture under natural light would help. What is the N-P-K ratio of the nutes you are using? What's the pH of you nute solution, what's the ppm, how often do you feed/water, and what's the pH of the run off. Almost all deficiencies are caused by a pH problem, curled crispy leaves are usually caused by heat, light too close, or over-feeding. Go to plant problems on the first page of www.growweedeasy.com and you might find your problem - look at nitrogen deficiency. Hope that helps.
Looks like a nitrogen deficency of some kind mate. Its probably cause you have mixed soil an compost an tgen using nutes for one or the other
I don't have time to do searching right now but I don't believe that the bottle is actual plant nutrients... Is there an NPK? Ingredients? J
I looked it up and the N-P-K is 0-1-0. To the OP - you are literally starving your plants - you are giving them no nitrogen or potassium at all. It's just a supplement to be used in flower along with other nutrients - not by itself.
classic undetfeeding of epic proportions...the plant reacts by cannabilizing itself taking the existing nutrients out of the leaf and shooting that to the top of the plant which probably is still green..as this is a natural defense mechanism plants have when they don't have enough food .although hard to see in pics....I would feed immediately...make sure the runoff ph is in the correct range those yellow leaves won't recover so you can take them off....but don't take of leaves that still have some green until you know it's fixed...otherwise she will pick apart other healthy leaves in order to promote new growth at the top.... also....when you start flushing (7-10 days before chop time) leaves will naturally turn this yellow as you are giving it no fertilizer....which is necessary at the end but you know why it's happening .....yellowing should not be happening when you don't know why... hope this helps good luck dude Sent from my SM-G600FY using Tapatalk