Nutrient Burn for these autoflowers from hot soil?

ChalupaBatman

420 Member
Im growing three autoflowers right now in a grow tent, 2 northern lights and 1 blue amnesia. I am having trouble with one of the northern lights and one of the blue amnesia. I believe what I am seeing is nute burn due to the curling leaves and the yellowing. Against my better instinct I put these in vigoro potting mix soil from home depot which I think may be giving them too many nutes as they are less than two weeks old. I went ahead and flushed the 2 with 3x distilled water and checked the run off to make sure its between 6-7ish PH and with a ppm below 300. Wanted to check if anyone on the forum had any more suggestions or ideas; my plan was to start feeding them in a few days potentially at 1/8 strength twice a week. Just to nutshell the main questions here, thank you:

1. are these photos in conjunction with the context indicative of a probable nute burn?
2. at day 11 is this growth a bit slower than usual or alright?


Below is my environment:

1. start date: 9/11 (kinda bad luck I know)
2. watering schedule: 1/3 cup of tap water every day or so
3. light: vipaspectra 300w at 24 inches as specd
4. soil mix: vigoro potting mix
-25% perlite added for the plastic pot
-20% perlite added for the clay pot (clay plant seems worse)
5. temp and humidity: ~80F ~60-70%RH
6. extras: fan hitting them constantly to strengthen stems

Blue Amnesia
blueAmnesiaVigoro.jpg


Northern lights
northernLightsVigoro.jpg
 
Nute burn just hits the very tip end…. I’d start with watering too frequently… since the soil is pre nuted then every time you water - by default you feed her more nutes. Those seedlings can’t use 1/3 cup every day or so - suspect necrosis is caused by lack of oxygen to the roots, ph may be off too ain for 6.3

I don’t grow autos well but think you are a bit slow getting her out of the gate. Runoff tells you nothing useful. Typically you don’t want to transplant autos, doing so can stunt or stall the plant. Best to start autos in large final container at least 3 gallons in size but then you’ve got to learn to water differently... see link in Emilya’s signature…. How to Water Small plant or Auto in large final container
 
Ahh damn, I was wondering if maybe I was showing them too much love. It's weird because I definitely checked the soil to see if it was bone dry before adding water and it was. But the nute feeding by watering makes sense -- I never realized that. As for the transplanting I usually grow in the container straight but thought I would try something different this time.
 
I have to go along with what @Emilya mentions. The first thing I noticed was that there is way to much water being used. I cannot figure how those small plants in those containers are using up so much water that the soil is dry as a bone by the next day. As she said, the soil has to be dry from the top to the bottom.

And, as you are able to get the watering figured out you can work on bringing the Relative Humidity down. 60-70% RH seems a bit high and after awhile can cause a few other problems.
 
I’m in a similar place as you growing autoflowers for a couple years now. Emilya’s write up is excellent and what brought me to this forum. I just purchased a cheap food scale for $10 off Amazon to start weighing my seedlings to know if they need water. It’s going to be a game changer. Check out my grow journal , I’ll follow yours. Good luck and have fun!
 
Back
Top Bottom