Hey Everyone, I’m three weeks deep into my first grow. I’m currently using the BCNL Roommate grow box. I’ve been monitoring pH and PPM daily, but I’ve been having a hard time with my girls yellowing and getting brownish dots on the leaves. I try to keep my pH from 5.4-6.0. I have read that if my nutes ( I’m using future harvest, as well as sensi Cal-mag because my water is RO water)are correct, the PPM and pH should not fluctuate. But everyday my pH seems to increase. I checked two days ago and it was at 5.9 so I figured it was okay for one more day, but then I went back yesterday and it was at 6.5 and there was a couple very yellow leaves with brown (I’ll attach images below). I’ve read it’s common towards the end of the flower cycle but I’m not even half way through! The buds seem to be okay, but I don’t want to harm the plants or their yield. If anyone has any idea what could be the problem and how to prevent this? If I’m missing information please let me know!
Do you think it would be caused by the high pH? These are the nutes I’m using, not sure if I should create a foliage spray or add some more of one of these nutrients to the 16L res. Thank you very much for your input Mac
oh yea you might be right about pH ,,,,for some reason ive never had a pH problem or ever measured pH either ,,mac
You need more phosphorus, either that or that leaf didnt get light, hard to tell since your holding it. Your definitely over watering they are droopy try watering less.
Really? What growing medium do you use? I have a 12 week sheet that gives me week by week, how much of which nutrients to add to my water. Even with this sheet, I check the pH daily. And every day it increases sometime slightly, sometimes it spikes like it did the other night...
I will add some tonight, does applying extra phosphorus as a foliage spray work, or just add to the res? Also, I don’t know if it’s normal, but during the night it seems the leaves always drop (that’s when the picture was taken). I’ll attach a pic of how they look during the day! The roommate runs the water pump 5 minutes daily. I’ve measured and seen that within that 5 minute period, approx 200mL of water from the res is injected into the rockwool. I could shut the pump off for a day or two. Let me know what you think
i use a potting mix by Levington it contains around 4 week fed so dont feed till just after that is used up .some times i pot up in to fresh potting mix and that carries the plant through the the stretch when i flip light to 12/12 ,,,never have have any trouble ,,,,maybe a a bit short of N some times but no big problems mate ,,,mac,,
No if it was taken in the dark its normal amount of dropping, definitely a light related issue or phosphorus dificiency.
Okay, good to hear the nighttime droop is normal. Those leaves that I am holding, are towards the bottom, but I can see a progression upwards based upon yellowing of the tips. Yeah, come to think of it, could that damage the buds? For my final week I’m going to flush the plants and then last day or two stop all the light. The whole pH thing is seeming a bit tricky. I can’t get the right amount of nutes to keep the pH and PPM stable. Every time I need to add pH down it’s increasing my PPM and I’m not sure how that impacts the poor girls.
I will need to read up on coco! Can I implement that into a hydroponic system? Thank you for your time and input! I really appreciate it @Jhard1991
As the plant takes up nutrients the ph of the reservoir changes, and anything over a 6.1 ph makes phosphorus slower to access for the plant. You must remain between 5.5-6.1ph that is the safest place for nute uptake in any medium.
Coco doesnt require a resoivoir, coco noir is cocunut husk, I prefer the bushdoctor brand because it contains micro nutrients and perlite. I water each plant at 5.8ph and ppm based on what they need. I increase ppm slowly usually topping out at 1300ppm in week 5 and back down to 900 by start of week 7 and then flush. Coco allows you to use hydroponic nutrients while growing in a pot like traditional soils.
Do you have any pictures of the set up? I have about 2 cycles left of hydro nutes, so I wouldn’t mind branching off! I am trying to experiment and see what grows the best with the least amount of hiccups! I can show you how my mine looks if you’re interested
Just because it's a potted medium doesn't mean its organic, organic refers to microbial fed or naturally achieved nutes. Hydropnic nutes can be used in these mediums because they dont have a soil buffer to attach and hold on to, meaning each time you water your replacing and flushing out the nutes from the previous watering. This would be similar to clay pebbles as a medium only much better at retaining moisture. Use it with a cloth pot and you will have great draining and oxygen content for a pefect grow environment.