Burning Questions? I'm a bit lost with this one....

[Blazer420]

Hi Everyone,

I have a bit of a burning issue on my hands and could use some help.

The pictures below are of a HSO Em-Dog that is 4.5 weeks into flower. As you can see the tips of many of the leaves are crispy brown (maybe hard to notice in HPS). Before I get into the details a bit of some background.

The plant is...

under 1k HPS
in 7 gal Smart Pot
in VermiFire straight from bag
Getting EJ nutes, casting tea, and MaxiCrop
"day" temps 79 deg, "night" 69 deg
45% humidity
Tested soil ph 6.2

Now here is the issue. All the others in this group are in identical conditions and do not show the same tip burn. They all get the same nutes dosing, and watering. They are all the same distance (30") from the light.

This started innocently enough in that some of the old growth fan leaves started to yellow and became necrotic and fell off. It appeared at the time that the plant was just using up the remaining N in the soil. Some of the others have been doing the same, but to a MUCH LESSER extent. Then the tips started on a few leaves and now are on most leaves at bud sites. Each time I visit the girls the tips look worse.

If you look "deeper" into the photos you can see some of the lower bud sites showing the same symptoms.

Thoughts, ideas, questions?

Thanks,

B-

 

[Spimp]

Hi.

To me it appears to be classic nute burn tips. Maybe this ones just more sensitive.
Have you tried backing off on her any since it started?
But ive never grown with a 1000w light, only CFL's. Maybe someone more experienced with those nutes and stuff could chime in.

 

[The303Stoner]

As far as I know I'm pretty sure that Vermi Fire is a stand alone product and you should only water.

 

[Blazer420]

Since it started all plants in the room have had only water. I only feed every 8 days. The plant has seen no EJ Grow for a few weeks so if its nuts burn I'm not sure that it would have been caused by N.

If it helps, this particular plant has the largest flowers by far. It almost looks like she is 2 weeks older than the others.

Thanks!

B-

 

[Blazer420]

I have been using VermiFire for some time now, and i have not found that to be the case. It contains enough "stuff" in it to keep for a 3-4 week veg depending on the strain and its hunger, but after that you need to start feeding the "herd."

As far as I know I'm pretty sure that Vermi Fire is a stand alone product and you should only water.

 

[shottafire]

Yeah it looks like burn a bit but not a big deal.

what are your feeds like?

I use vermifire as well and like the stuff very much. But it needs to be fed eventually.

 

[Blazer420]

Mixed exactly as instructed by EJ. I feed roughly every 4th-5th watering.

This may just be a very sensitive pheno since the others aren't sowing anything close to this - more like typical stuff you see as you are approaching harvest.

Thanks!

B-

Yeah it looks like burn a bit but not a big deal.

what are your feeds like?

I use vermifire as well and like the stuff very much. But it needs to be fed eventually.

 

[Dmaui]

Try flushing. Salt build up is probably burning. It can cause lockout to.flush then give 1/4 nutes the following day. When you flush emember the ph of your water and collect some runoff and compare the ph and ppm before and after. Soil tends to become acidic

 

[Blazer420]

Salts? I'm running EJ and didn't think that there were slats in it to build up...

Try flushing. Salt build up is probably burning. It can cause lockout to.flush then give 1/4 nutes the following day. When you flush emember the ph of your water and collect some runoff and compare the ph and ppm before and after. Soil tends to become acidic

 

[Spimp]

Every thing is a 'salt'. Micro's, Macro's its all measured as 'salts'.
A basic ppm reading that shows 500ppm bascially means 500 parts of 'salts' per million.

 

[Dmaui]

4.5 weeks into flower is why I mentioned it, if you haven't flushed atleast twice there's your problem, salt build up. Easy way to tell tho is check the runoff when you water( ph and ppm). Wouldn't trust a soil ph tester. What is the ph of your water? I use ph down with my 7.0 water. Usualy when I flush I use like .1 or .2 ml of ph up at 4.5 weeks flower 10 gals of water per 5g. What I am sayings is, if you've been useing ferts and ph and haven't flushed your mefium has a build up salts or is either becomeing to acidic or neutral

 

[Blazer420]

I get it. My mistake. I was thinking of the term "salt" as it applies to chemical/man made nutes. I've not heard it used in reference to organic nutes before, but you're absolutely right.

Thanks!

B-

Every thing is a 'salt'. Micro's, Macro's its all measured as 'salts'.
A basic ppm reading that shows 500ppm bascially means 500 parts of 'salts' per million.

 

[Blazer420]

Those are some very good points. No, I haven't flushed - and never have until the last 2 or so weeks. I did just test the ph of the runoff (water - no nutes) and it was 6.9 with a ppm of 732. 732 of what though? I water with RO and it could have picked up anything in the soil I suppose...

Thanks!

B-

4.5 weeks into flower is why I mentioned it, if you haven't flushed atleast twice there's your problem, salt build up. Easy way to tell tho is check the runoff when you water( ph and ppm). Wouldn't trust a soil ph tester. What is the ph of your water? I use ph down with my 7.0 water. Usualy when I flush I use like .1 or .2 ml of ph up at 4.5 weeks flower 10 gals of water per 5g. What I am sayings is, if you've been useing ferts and ph and haven't flushed your mefium has a build up salts or is either becomeing to acidic or neutral

 

[Blazer420]

I did have some interesting news about this whole thing.

I have a friend that works for the local Ag bureau and he sent a sample of my soil into the lab. We took samples from all the plants. When he called me, he didn't have the results in front of him, but he essentially said that all the other samples were fine, but the one from the Burning Bush had very high levels of calcium and potassium in it, and he believed that Ca was "chemically" locking out K and what I'm seeing is not nute burn but rather a K deficiency.

If that is truly the case then I'm still stumped about why it hasn't happened to any of the other soils or plants. Everything under my control is exactly the same for all the plants.

Again if this is all true, a flush is seriously in order. The question is should I do it to just the one or all of them? And as a secondary question does anyone have any tips for a big flush in Smart Pots? It would seem that when you undertake a "corrective flush" that since the water can drain from everywhere on a Smart Pot that it would be difficult to evenly "wash" the soil since the water isn't forced to go straight from top to bottom.

Thanks!

B-

 

[Perfect Sun LED]

Not sure if you said you always water with RO water, but if you water with tap water, then that could cause cal build up if your tap has a lot of it.

Not sure why it would only effect one plant.

I always water with just water or water plus cal mag between feedings. I never use above 800ppm, I mostly stay with 700ppm at highest. Every few weeks, I water with drip clean and get a good run off. I always water until I get some run off.

 

[Blazer420]

Yup, always RO water. The plumber that installed it couldn't understand why I got such a big one "for drinking water and 2 ice makers" and why I wanted a manifold valve system near the storage tank. But that is another story...

I did do a pretty serious flush with a very small amount of yucca extract in the water and a significant de-foliation of the affected growth.

Thee plant sure seems to be responding well. Suddenly the flowers are swelling and the "burning" seems to have stopped and certainly isn't spreading (I left some leaves as a baseline indicator of the results of the flush).

I was worried I was going to have to chop this plant REALLY early to save at least something, but for now it looks like it might go all the way. Who knows?

Thanks!

B-