Last 4 grows very successful in coco/perlite using frequent fertigation ala “coco for cannbis”. Been using “cloud coir”, link below. Note, even though “ready to use” I always wash in PH’d cal-mag water mostly to remove some “coco sludge”. Always water with RO water PH’d to 5.8/5.9.
Fast forward a bit, wanted to start new autopots in one tent and normal coco/perlite in the other. Out of “cloud coir” so I ordered FoxFarms "cream of the crop mix’, another 50/50. Found the mix odd as it was much darker (blackish) and had a noticeable “earthy” smell.
Well, one of the autopots started to yellow/brown on top leaves like an immobile deficiency about 2 weeks into flower. Younger plant in air pot started to get large brown spots on leaves that followed the new growth up the plant. As part of triage, someone asked me what the runoff PH of the air pot plant was (I normally don’t’ check PH out - just PH/EC in and EC out). I was very surprised it was 4.2 (on a recently calibrated meter).
Then I made a 1-1 slurry of both mixes. PH of cloud coir was 6.5, PH of FoxFarms was 4.1.
Was not expecting that in a pre-buffered ready to use mix.
So. The question is does initial PH of a coco medium matter at all in either fertigation or autopot scenarios? Or maybe I’m over thinking this…
YES !!! I have had the same experience with Fox Farms Coco mixes. Now I run 3 parts Fox Farm 70/30 Coco Perlite and 1 part 50/50 Cream of the crop. Once mixed, I have to rinse FOREVER to get clean water out. Then I precondition with full strength ph’d Calmag, Then I precondition again with whatever nutrient solution the plants are currently accustom to. My last order(3 bags) the 70/30 mix was moldy so I had had to eradicate that as well. I’m going to start looking for something different.
I am currently using the foxfarm 70/30 mix. It is my second run with it or coco in general. I currently have 6, 3 week old plants in 3 gal bags. Eventually headed to auto pots. I water in at 5.8 with my nute solution. For 4 days since transplant with lots of run off, my run off is 5.1 to 5.4 , ppms out are nearly identical to input at 800 so that is ok. The plants seem happy, but in the back of my head I am wondering if the coco is messing with the ph?
I did a few nute solution soaks before transplanting into the pots. First run went fine, but after reading your comment, I wonder if I may have an issue. @OldNailPounder
Thanks! It’s great to hear (well not really great) that others have had issues with this product. Amazing what just one variable change can do to your grow. I got rid of the half bag of the FoxFarms stuff and went back to Cloud Coir, ordering 3 more bags to make sure I have it handy. Got two 2-week olds in the Autopots top watering waiting to turn the system one. Looking great. Best of luck with the soil prep, I don’t have the patience.
Hi, Coco is “supposed” to be relatively PH neutral and hold on to those properties. That’s why I was surprised my FoxFarms PH’d at 4.1. I’m still trying to understand the actual implications of that in grows. Best of luck.
I just did another big water/feed to run off. Ph was at 5.1 on almost all of them. I decided to move them to sink and hit them with 6.5 ph tap til I finally saw run off of about 6.0. I am not sure how bad low run off is as the plants seem ok. But in flower i need higher ph in flower. I decided to try and fix it today. Will see when I water again tomorrow. Final ph for all 6 was 5.8 to 6. I then fed again at 700 ppms. I just don’t understand how coco can pull ph so low. I have no salt build ups. In ppm just about equals run off ppms. Growing regs so can’t move to auto pots til males are identified. No room for those pots with 6 plants. @cc014572
So cocoforcannabis.com is a great resource for growing in coco. He recommends NOT monitoring output PH when fertigating. I never checked my ouput PH except this one time. Since Coco is supposed to be PH neutral, I was just trying to figure out why foxfarms was way low and if that mattered before the grow. Best of luck and please keep me in the loop on your grow!
I watered again at 5.8 and got 6 out. Seems better after I gave them a pretty big watering yesterday. Guessing coco was dirty or something, even the run off color is lighter now. Who knows, but all seems well.
I have another bag, I will give it a better prep next time, but totally defeats the purpose of buying already prepped coco.
I just never got to the point where I was aggressively trying to save the plant. Just sacrificed her when my preferred coco came. Figured why waste 2+months of time. But I have more seeds than I could ever grow anyways. Take care.
Or maybe I’m over thinking this… 
