I’m scratching my head a bit, trying to dial in the nutrients for my OG Kush feminized photo. Growing in a climate/RH controlled tent. Temps hover around 65-72 day and night. RH is ~60%.
My plant is about 6 weeks old.
I use silica, Jacks 3-2-1, in HP promix soil, 5 gal fabric pot, watering 1.5 gal every 3-4 days @ 6.1-6.2ph. My last few feeds have ranged from 1300-1600ppm.
I know this is extremely high, bc I realized I have been incorrectly converting ppm to EC.
The plant is showing, to my untrained eye, no signs of stress, or nute burn, is growing, really, but she doesn’t hold vigor in her leaves for long before looking limp. I was afraid I was overwatering (despite checking the soil several inches down before EVERY feed): However; I gave her a few extra days and used a water meter before feeding today.
Today’s feed numbers: 1090ppm, 2288us/cm, 6.3ph
Runoff numbers: 1920ppm, 4085us/cm, 6.15ph
I’ve included pics of plant prior to today’s feed. As I mentioned, I gave her 2 extra days to make completely sure she needed to be fed.
I’m confused bc my last feed, I was routinely feeding in the 1400ppm range, and had a hearty plant with a great yield.
I’m guessing genetics play a big role here, but could I please get some advice on the best way to proceed? Like I said, she doesn’t ever seem unhappy, just doesn’t hold any vigor, and obviously she isn’t getting the nutes she needs given those astronomical runoff numbers, correct?
I rely on this community so often, so thanks! in advance.
Looks like she’s a heavy feeder , as long as you don’t let it wilt for too long it won’t cause permanent damage . Be careful is all , starving for too long can be a major stress . Peace .
I’d be willing to bet your headed for nutrient lockout from your numbers, I grow in Promix as well. At your EC, the PH in runoff is already dropping, indicating salt buildup, I would mix my next feed at 600 ppm and 6.0 ph. Promix should be in the 5.9-6.1 range. It may take several gallons of water through them to completely reset your media. Run it through until runoff matches input, then let them dry back good, Promix should feel light like a loaf of bread before you water again. Then adjust feeds to maintain 800-1000 ppm in runoff. They should take off after that. I’ll tag you in my journal, all Promix grows except a coco run I did.
I had been keeping my ph in that promix range, then I got in my head about what was happening and boosted it a bit this feed, thinking I was maybe shutting out available nutrients.
I run mine at 6.0 all the way through, love my Promix! Just remember to get at least 25 percent runoff and you will not likely have to flush again. I feed mine at 1.2-1.4 95 percent of the time, I go up first few weeks of flower, then drop back to that. Mine seem to do ok with it. I am running Mega Crop one part now, but ran jacks last few grows before that.
Yes, 600-700 ppm. Feed every watering, plenty runoff. Numbers will stabilize after a bit and they will get happy and not wilt. I looked back and saw your in 5 gallon bags, you will have to give them 2 gals each to get proper runoff, I give them 1 1/2 or more in 3 gallon bags.
Dont know why it wont let me quote you but I wanted to comment about your temps and humidity.
You said you run between 65-72 all the time. This is actually kinda cold for a vegging plant. Vegging cannabis enjoys a somewhat higher temperature then 72. Try running warmer at lights on. Closer to 80 degrees. As high as 77-82 even. Then run down to about 72-75 in the dark. Think of the veg period as spring time weather warm/hot and moist in day, cool/cold and moist at night. Having such a cool environment is for sure having an effect on the temp at the root zone. Cold roots cant drink as much, if they arent drinking then they arent eating. Humidity seems fine, you could even come up a lil more, say 5% as long as your air circulation and exchange is on point. Once in flower come down closer to 50-55% to help keep molds at bay.
She looks overwatered in the pics. Are you sure you arent overwatering? If yes what about your mediums makeup? Got enough perlite?
You got alot of advice on feed so im not even gonna mention anything, she looks like she wants you to do something for her and she isnt gonna move till you get it. Total power move on her part..id cave and give her what she wants no matter what it is!
I agree with Growdoc on ph, found my best results between 5.8 and 6.0.
I think you would see more rapid development if your lights on canopy temps were in the 80-82f range. Led lights don’t heat leaves like hid bulbs do so you would typically want air temps a little higher to help get leaf surface temp up. If you start getting too much below 80 you can usually notice plants will stall some.
I am using led lights. I live in SoCal and currently my day temps are 80 and lows 71. But that’ll likely drop by early next week, more into the mid 70s to low 70s. Not sure how I can boost temps other than maybe raising lights and upping %. Worth a shot.
I can control RH and will increase.
I could sense she wasn’t happy, but couldn’t quite put my finger on it. Grateful for this resource to connect.
Re: overwatering: I’m confident I’m not, but I don’t want to be stubborn and overlook. I use promix in a fabric pot and I do a finger test to knuckle in multiple spots around the pot.
The pot is so lightweight before I feed. It doesn’t feel like any real moisture is being held at all by the time I feed. But I got out the moisture meter to be
Some pics have drooping leaves some have upward prayer leaves seems like drooping leaves pics need water and upward prayer leaves are happy and been fed, were there actually spots or brown/yellow leaves?
No spots or browning/yellowing (yet anyway). I’ve thoroughly examined the leaves (checking for pests).
It’s mainly that her leaves don’t hold vigor very long after feeding, like really soft looking before she’s ready to feed again. and those crazy high runoff numbers. Which felt related; not getting enough nutes or something in that vein (but needed advice from more experience to know if that could be true).
I fed her Friday morning (lights out 3p-9p). Here’s photos of her yesterday and today respectively.
I agree with upping your daytime temps. I wouldnt worry about nighttime, my tent is 63-65f at night and 80-83f during the day.
Out of curiosity I measured my soil temp ~5-6 inches down. It was 64.5f. This is with a floor temp of ~71.5f and canopy air temp of 81.5f(my tent is on tile the floor gets colder at night, maybe ~68f or lower).
If your plant looks like one of mine does(#1, check my grow) when the soil is still wet it could be “rootbound” and youll have to water more often than you otherwise would. Or you can pot up to a bigger container. Ive had bigger plants flower in a 5 gallon with no issue before but its something to consider. I would make sure temperature is under control before changing anything else though.
I’ll tag you in my journal, all Promix grows except a coco run I did.
