Nute Excess/deficiency, normal?

nitroboi

Member
I wanted to get your opinion on some yellowing leaves/burnt tips etc. I can't tell if it's an excess or deficiency of nutrients, or if it's normal for this stage. I used 1lb NLS Autoflower mixed (super soil concentrate) with Ocean Forest in the lower 1/3rd-ish of a 5gal fabric pot. I use bottled Spring Water - pH was 6.3. I had to switch from buying smaller bottled to bigger 1gal bottles that were from a different spring where the pH was 7.8 (Good thing I checked), so I pH it to roughly 6.5 using Earth Juice. Its organic so I do not water to run off, thus is hard to check the soil pH, but I have pH'ed the water every time. The only other thing I have added is Recharge (microbes/fungi) every 3rd watering. I am roughly on week 4 or 5 of flowering. I am running a Viparspectra XS1500 about 18 inches @ 80% 18/6. PPFD is roughly 600-700, which puts my DLI between 40-45ish. It was a bit higher and I lowered it recently because I was seeing some white tips. It's a White Widow Autoflower. I have attached a bunch of pics.

Thanks!
 

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nitroboi

Member
Ive decide to go with my gut and put it down to a deficiency. Judging by the fact that its slowly progressed bottom up, …..and other reasons my intuition is unable to articulate. The tip burn is what throws my off. Although from reading, some deficiencies cause it. This is one Con for growing in organic “water till harvest” soil - less control. If i were using bottled nutes, i could judge easier. I bought some Dr Earth Flowergirl for this reason. Itsadry amendment so maybe i’ll give 1/4 on next water and see. Then really really hope its not an excess and it makes it worse.
 

nitroboi

Member
It looks to me like light stress, They will show deficiencies and toxicity, Drive you crazy..
www.growweedeasy.com/cannabis-plant-problems/light-burn
yeah.. i recently turned the light down a bit - had the same thought. Heres what throws me off.. mutiple middle of the plant leaves yellowing with alot of burnt tip. The one that is really burnt up is on the bottom

“If you see light bleaching and unhealthy discoloration only on the parts of the plant directly under your grow light, or only on older leaves that are exposed to the light, it often means it’s too bright for your plants and you should move your grow lights further away!”

- now the bottom leaf could just be the plant cannabolizing it because its not getting light but
 

HydoDan

Well-Known Member
Light stress causes a defensive mechanism.. They move nutes to protect the new growth..
The burnt tips are from prolonged exposure..
I would cut the light in half for a few days and give her a chance to recover.. Feed normal amounts..
Good luck..
 

nitroboi

Member
Light stress causes a defensive mechanism.. They move nutes to protect the new growth..
The burnt tips are from prolonged exposure..
I would cut the light in half for a few days and give her a chance to recover.. Feed normal amounts..
Good luck..
i can cut it back more - i dont feed anything;) thanks for the 2 cents
 

nitroboi

Member
In the pursuit of science I went ahead and flushed a small amount of water out of the pot (less than 200ml). Came out pH 5.9ish 720ppm. I then put another 300ml of water through in and the SMALL amount of water that came out - barely enough for a reading - pH 5.9ish 1050ppm. pH seems slightly low, although theoretically, if the textbooks are right, the soil microbes can feed a range of nutes at a pretty wide range of pH. In any event, good to know. In hindsight, I wish I would have flushed with 6.8 pH water instead of 6.3 I will just monitor and use pH 6.8 water next watering.
 
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nitroboi

Member
I ended up contacting the Nature Living Soils guys to see what they thought. They recommended their standard flush to 'reset' the soil. I flushed with ph 6.8 water with 1/2 dose of cal/mag. pH came out 6.1-6.2ish. I also added 8oz of Recharge. I... dont think i see a positive change 72 hours later. It actually seems to be getting worse - spreading to other leaves. I added another half dose of cal/mag to this watering (last night). I think she is actually in week 5 of flower (breeder estimates an 8 week flower) - I cant help but wonder if its just running its course. My gut tells me something is wrong but...its an organic grow.

There are 2 plants in these pics...some of the other ones leaves are in the pics.
 

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sonnyjim

Member
A pic of the whole plant would help but looks like its pulling N from the fan leaves and older growth, normal when running low on N in the soil. A top dressing of blood meal helps, takes 7-10 days to notice a difference. Beware if it is low on N, the more you flush the worse it will get. Maybe raise your light a little or lower intensity too.
 
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