Identify problem marijuana leaves

Can anyone tell me if this is burn or deficiency or what?

It looks mostly like burn, but if you are feeding a balanced nutrient and are sure you are not over feeding, it might be a deficiency or “lockout” due to pH.

I’m betting mostly it is nute burn, or an accumulation of too many nutrients in the root zone.

A pH and EC/TDS reading of the root zone could help us help you, maybe of the runoff after feeding with pure water. Or watering only without feeding, rather. Testing the run-off water will give us a general idea of what is going on in the roots zone.

you can also test your soil as described here in Robert’s blog:

check out these tools if you haven’t already done so:
http://support.ilovegrowingmarijuana.com/c/ilgm-official-sonsors-buters-guides/ph-ec-tds-meters-pens-controllers

hope this helps,

MacG

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macGvy: would a PH issue cause rust-brown spots to appear on leaves? Have my PH at 6.2, but I ran out of vinager, so the last 2 waters have been 7.4 (which is what my well water is from the tap)

TIA for your advice.

would a PH issue cause rust-brown spots to appear on leaves? – Yes, yes it most certainly can.

It looks exactly like that is what is going on in your garden.

Check this out:

Hope this helps,

MacG

Thanks for your advice (: Do you think Sul. Acid works better than vinegar? Thanks Again for your help

That is exactly what I said in the other link. Vinegar is not a very good pH down at all.

Thanks, I missed the Sulfur. Acid link…Got it now…Thanks Again for your help. Much appreciated

I am growing a White Widow in its 8th week of flowering. In the last 5 days some upper family leaves have been drooping and turning yellow with brown spots. Also some of the leaves around the Cola have done the same thing. I cant raise my LED lights any higher…any suggestions…Is this a nutrient deficiency…toxicity…light burn ??

Thank-you

It might be light burn, but light burn is more of a fading, if it is from photo-inhibition and not an actual heat burn.

Especially as you mention the yellow with brown spots. This sounds more along the lines of a toxicity, maybe pH or nutrient salt toxicity and deficiency. Often pH not only can make some nutrients more available (even to the point of being toxic) while also making others unavailable, some nutrient toxicities in and of themselves can cause other nutrients to be locked out. Sometimes even without the pH being out of whack, some nutrients can build up to the point of creating a toxicity, this is why many growers periodically flush their soil.

I’m not convinced it is light burn, a picture could help, and any other additional info, such as pH numbers or TDS/EC numbers present in your soil or run-off.

happy growing,

MacG

Thank-you for your response …I neglected to mention we are using a Hydroponic grow box. Could adding hydrogen peroxide to the water in the correct amount and strength help this situation ? We also have a Blueberry that hasnt shown any visible growth for 2 weeks. We checked the PH of the water and it was around 6.3 We are first time growers and now realize that its best not to grow 2 different strains in the same box. We are using the Cash crop 4.0 from Dealzer.

Thank-you

OK, hydro pH should be about 5.8, so your pH is a little too high. The pH can range, it should be as close to 5.8 but it can range from about as low as 5.4 to as high as 6.2 as long as it doesn’t stay at these far edges of the range for too long.

So yes, the pH could be that main thing causing your problems, Something else to keep in mind, especially with deep water culture hydroponics is the water temperature. In hydroponics in general, the water temperature is very important because the roots need oxygen and water that is too warm, the water can’t hold enough dissolved oxygen, and this too can cause nutrient uptake problems similar to pH problems. Ideally, if at all possible the water temperature in DWC (the type of hydroponics these grow boxes usually use) the water temperature really needs to be below 72F, the ideal temp range is about 68F to not higher than 72*F as the amount of dissolved oxygen will drop dramatically above this temp.

Some hydrogen peroxide might help keep bad pathogens at bay and can increase D.O. levels in the water temporarily, but it would not be good for long term.

~MacG

I filled out a support ticket PLEASE is anyone could bounce some ideas off, that would be much appreciated.

I have no idea where you filled out said ticket what seems to be the issue?

Hi all, I am a total noob ( this is my second plant after killing my first!) I don’t have half of the information needed for a support ticket. I have read through the “guide to sick plants” thread and I feel as though there could be half a dozen problems!

Can anyone identify what the issue might be from these dodgy phone pics? Much appreciated! :slight_smile:

looks like a toxicity but you would need to fill out a support ticket to narrow things down some
Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so = NA

Strain; Type, Bag seed, or NA

Soil in pots, Hydroponic, or Coco?

System type?

PH of runoff or solution in reservoir?

What is strength of nutrient mix? EC, or TDS

Indoor or Outdoor

Light system, size?

Temps; Day, Night

Humidity; Day, Night

Ventilation system; Yes, No, Size

AC, Humidifier, De-humidifier,

Co2; Yes, No

Add anything else you feel would help us give you a most informed answer. Feel free to elaborate, but short, to the point questions and facts will help us help you smile

Strain; Type, Bag seed, or NA
Northern Lights autoflowering feminised

Soil in pots, Hydroponic, or Coco?
Soil in pots. Combination of potting mix, perlite and some blood and bone

System type?
?

PH of runoff or solution in reservoir?
Don’t know

What is strength of nutrient mix? EC, or TDS
Nutrients are an all-purpose fertiliser, mix is 50mL of concentrate to 9L water.

Indoor or Outdoor
Indoor - in a grow cupboard

Light system, size?
300W LED Alien-type light, running 20 hours per day on a timer

Temps; Day, Night
It’s summer, so has been ranging from 25-35 C in the day, and from 15-25 C at night

Humidity; Day, Night
Don’t know - thermometer/hygrometer is on order!

Ventilation system; Yes, No, Size
I have an exhaust louvre for passive air changing. I am installing a intake/exhaust fan this week

AC, Humidifier, De-humidifier,
No

Co2; Yes, No
No

Sorry I can’t provide more information - please refer to my “noob” comment earlier :slight_smile:

2 things that jump out at me right away not knowing your ph and the fact that you are using nutrients in a mix[quote=“cheeky176, post:36, topic:2028”]
Soil in pots. Combination of potting mix, perlite and some blood and bone
[/quote]

which is amended with natural fertilisers and far too strong of a mix for a young plant. You should also have some idea as to the ph of your soil and nutrients mix
What you are looking at is severe nutrient burn (toxicity) I can’t be specific as to cause aside from feeding a dose I wouldn’t give to a 2 month old plant in veg which is in a soil which has nutrients already.
All I can logically suggest is re-pot skip the amendments and use ph tester on your water adjust ph to 6.5 give plant some time to hopefully they will unstall in a few days.

Edit: lets get some other opinions as well @Paranorman @peachfuzz @kabongster Flush or re-pot?

aren’t those slow release N & P organics? so a flush would be temporary?(I don’t know, not a blood bone meal user)
it’ll be a long grow with an unresolved soil problem.
repot, skip the amendments.
B-1 for repotting, super thrive, liquid karma will make the transition easier

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There’s nothing more that I can really add… @Donaldj , @kabongster have givin you the best advice as to what you can do to solve this problem … you should really try to acquire the meters and testers that you need to have a successful grow or else I’m sure that your problems will carry on into the future …good luck

:v::sunglasses:

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Thank you for your assistance. The hygrometer has arrived and the humidity ranges between 30%-50% - it’s been a dry old summer.

Thank you again for your advice :+1:

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