Plants are a little over 2 weeks old from seed, straight promix hp and distilled water only, I started them with CFLS and after a week old i overwatered And growth slowed greatly after drying out they went back to being fine but the lower leaves are discolored and have spots. I switched to 300 watt MH and CFLS a few days ago but the spots were there way before that and have gotten worse. The first set of round leaves have stated to yellow on some off the plants, is it just time to start nutes? Sent from my iPhone using Grasscity Forum
looks like nutrient burn. What soil mixture are you using? It may be too hot for them Sent from my iPhone using Grasscity Forum
It is only straight promix hp, no nutes have been given and only distilled water, ph should be dead on shouldn't it? Sent from my iPhone using Grasscity Forum
In a perfect world yes but we are growing cannabis in an imperfect one lol (stoner revelations). Check your soil ph and runoff ph and get back to us. Sent from my iPhone using Grasscity Forum
Runoff is 5.2, that's the very first runoff as I kept "flushing" I stopped when I got about a 6.2. I was "flushing" with 7.0 ph distilled water I checked it also Sent from my iPhone using Grasscity Forum
All new growth and other leaves are fine it's only some of the very bottom leaves and only on about 4 of the 8 plants I have going Sent from my iPhone using Grasscity Forum
If first run-off was 5.2 it was definitely much lower. Does this mix say it has added nutes? Next time they dry, give them time, and flush again ... you'll probably need to once you check run-off again. And, @ 6.2 you'll still be missing some Ca and Mg uptake. http://hydro-heaven.com/yahoo_site_admin/assets/images/ph_Chart_3.208114926_std.gif
I believe the mix has nothing at all but I will check the bag, I do know it has lime but obviously it isn't working Sent from my iPhone using Grasscity Forum
You check the run-off with each water through, collect about 10% and test the ph ... only way to monitor your plants health.
When your roots start growing they uptake ions and release toxins that drive the ph down with some substrates that contain peat, basically according to the elemental composition of the medium.
I understand that, but in my situation where my initial runoff was 5.2 and I was flushing with 7.0 distilled, would you have just kept flushing with the 7.0 distilled? No reason to use ph up or down if I'm using that water right? And if I'm using my untreated well water which is around a 6.0 I would wanna use some ph up and get the well water to about a 6.6 or 6.7? And then water/flush with that? Everytime you water/flush do you continue to do so until you reach the runoff ph level you are looking for? Sent from my iPhone using Grasscity Forum
And what number am I looking for as a "perfect" ph run off number, THe very initial runoff and what I want to shoot for and end up with? Sent from my iPhone using Grasscity Forum
Also will dolomitic lime help keep my ph more stable and closer to where it needs to be? And if so how much would you mix with each bail of promix hp, 3.8 cubic feet I believe Sent from my iPhone using Grasscity Forum
give them some food and backoff on watering...ph nutes to 6.0-6.5..I shoot for 6.2 give or take..promix has lime in it so you should be good
I have a feeling not enough tho, last grow it stayed pretty stable up until about half way thru flower, then seemed to go all over the map like there was no lime at all Sent from my iPhone using Grasscity Forum
Top dress the pots with Dolomite lime, a tablespoon or so per pot size. Takes time though. Or prepare a pot for next grow by mixing it through and through and let it be awhile. Ph problems are a pia.