This is my first grow so I'm definitely a newbie... 4x Fem PPP from Nirvana They are under a 400watt MH (light is 18in away), temp is around 75-77 F, humidity has been around 45-50%, water pH is around 6.5-6.8 I just noticed some brown spot on my plants (see pics) and was wondering if this was normal. I read somewhere that this is usually an indicator of P deficiency but didn't know if was anything that I needed to worry about. I read that maybe should I maybe lower the pH of my water next watering, is this true? Any advice on the brown spots or anything else would be greatly appreciated. I attached pics of my 4 plants and some random pics of my grow room.
First off, nice little space you've carved out for yourself! Brown spots on seedlings. These are way to young to be having a nutrient deficiency. IMO this isnt normal. Can you tell us about the soil? Is it premixed with any nutrients? Have you added any nutrients?
Might want to check your runoff ph, I suspect it may be really low. Have you added any nutes? What is the age of them? They shouldn't be trying to feed yet, but lots of light can cause them to start using up calcium & magnesium and if the ph is off spotting like that can occur. Just a guess, hope it helps you in the right direction.
Thanks alot for the feedback... The soil I used was MG Organic, MG perilite, and Hoffman's Vermiculite. I mixed my soil in a 2parts soil/1part perilite/1 part vermiculite ratio. The perilite has a very slight amount of nutes in it (Total N - .04%, Total P - .01%, and Soluble Potash k2O - .06%). I read MG sucks but I really had no choice based on where I live. My plants are 6 days old from when they first showed their faces above the soil. I planted them too deep so they took an extra day to break through. I haven't added any nutes to my plants yet and wasn't planning on it for a while at least unless the majority advises otherwise. The water in my area has a PH of about 8 I used some muriatic acid to bring it down which is approx 40% HCl and 60% H3O+ I think...there may be a tiny bit of Fe in muriatic acid but just a very slight amount (sometimes you get a salt on the inside of the lid...FeCl makes the most since). I have just been using pH test strips because I got them free and the pH of the water going into my plants was about 6.5-6.8 and the runoff was slightly more basic at about 7.0-7.2. Planning on buying a digital pH tester but I wanna see if I can just borrow one from my school first. When I checked my plants today the spots seem to not be as bad but it could just be me...I will post pics in a couple days to compare but any other advice would be awesome. Thanks a ton for the help!!
Well they appear to right on track as far as size for their age. However this could get worse as they age. IMO the vermiculite could be causing this pH problem in your runoff some vermiculite deposits have a pH from 7 to 9.5. Consider lowering the pH of your water to compensate and bring it down to the 6.5-6.8 range. Once you get your pH under control and the problem is still around then you can get a true diagnosis. However, in my experience and IMO plants of this young age are not affected as much by pH problems unless severe alkaline or acidic. They are more susceptible to root rot caused by over watering. Consider decreasing the frequency of your waterings. Best of luck
I agree with house055, they are so young that they shouldn't have ph probs unless it's severe either way and it doesn't sound like it if runoff is around 7. I'm afraid the other suspects may be in the fungus family (hopefully not). I'd let them dry out pretty good and see if they don't clear up the next few days. If not post some new pics and perhaps a 2nd look will help narrow it down some.
i'd say vermiculite causing watering issues. there is no need for vermiculite using MG organic. It retains water well and needs perlite to break it down to acceptable levels. you are canceling out the perlite by using vermiculite.
Water droplets act like prisms on young leaves. They focus the light like a magnifying glass and burn in tiny little spots into the leaves actually pretty quick. If you've been misting your plants then stop. If not then it's the soil. Young plants don't need nutrients and that soil is loaded. They will pull through, just let the soil get totally dry and then give them a good saturation with a bunch of run off.
I have been misting my seedlings because my humidity was low and then stopped once the problem spots came up so I'm wondering if that is what caused it...they definitely look better 2 days after I have stopped misting them. I am currently letting them dry out pretty well before I water them like you guys advised. I will post pics in a couple days once I do this. When my plants are ready to be x-fered to larger pots do you guys advise leaving the vermiculite out and only using soil and perilite? If so what ratio soil to perlite do you suggest? Thanks again!!
ive got a 20 gallon bag of vermiculite in my basement, I might never use it. prelite is awesome and works wonders. I wish i had a 20 gallon bag of perlite sitting down there. I have yet to use a soil that needs vermiculite. i run 20% perlite in all my mix.
When using peat-moss as the main soil medium I'd recommend always using atleast 25-50% pearlite in the mix, the more the better in most cases. I usually use a mix that includes vermiculite as well, in a ratio usually around 1:1:1, then other additives, organics and lime, etc...
Youve gone far beyond what some newb growers would do looking at your pics. Great job for a "newb" grow. Now tie it all together and get them in some good soil as soon as you can. Fox Farms, Humboldt, etc. Order online. Everything else looks great@!!!!!!!. Def a soil/medium issue IMO. Good Luck Brutha!!!!
I used a 50/50 mix of perlite to fox farms and had a load of Ca/Mg issues later in flowering. I think the perlite eventually absorbs too much salt and when you water the salts are dissolved into your new solution, which changes the TDS and leads to lockout of Ca/MG/K. I'd suggest using more like 20% perlite now. I personally gave up on mixing my soil and just got some coco. The stuff is effing epic. Check out my plants after 4 weeks in coco (the taller plants).
Well damn...I really wish I would have just bit the bullet and made a trip to the nearest fox farm dealer (about 2 hours away) and just picked up all the soil I needed. I guess I still could but im really nervous about x-fering seedlings as young as they are. I'm kinda hoping the problem solves it self and then maybe using fox farm or coco when I x-fer to 3gal pots. I'm really thinking that they are looking better...I will post pics when I get home from work in about 2 hours to see what you guys think. BTW thanks for all the compliments on my grow room and 2lazy your plants look awesome
These are new pics 8 days from sprouting...spots still there but I think they look better and there is no new spots on the 2nd set of leaves.