Darkening midleaf on new growth

[Dirrtybirdy]

Hi everyone,

In on day 2 of flower and I noticed this on some of my plants. I'm using 1.5 ec mega crop, .1ec sweet candy, .1ec bud explosion. Ph is at 6.0

Room temp is 75f and RH is at 64%.

I've looked through Joe's sick plant thread and didn't see anything that looked like it and also searched.

Thanks in advance!

 

[TanzanianMagic]

Hi everyone,

In on day 2 of flower and I noticed this on some of my plants. I'm using 1.5 ec mega crop, .1ec sweet candy, .1ec bud explosion. Ph is at 6.0

Room temp is 75f and RH is at 64%.

I've looked through Joe's sick plant thread and didn't see anything that looked like it and also searched.

Thanks in advance!

View Image
View Image

It looks very much like nutrient burn. However you should also check for mites.

The image in Ed Rosenthal and J.C. Stitch's Marijuana Garden Safer depiction of nutrient burn looks most like it.

 

[AgentPothead]

I feel like nutrient burn shows itself at the tips first. I'm seeing the newest growth yellow, but then the edges of the newest growth are super dark, almost purple, then it goes back to normal colors?

 

[Teddybrae]

I don't understand these nutrients. But for sure things aren't quite right in yr garden. Are you supposed to use all those Nutrients together? And your pH ... this is a soil grow, yes? ... is low. Needs to be 6.3 - 6.5. Are you testing soil or testing runoff? Testing runoff is useless.

 

[Lost in a SOG]

Micro nute def of some kind imo.. maybe lower the RH a bit..

 

[Dirrtybirdy]

I feel like nutrient burn shows itself at the tips first. I'm seeing the newest growth yellow, but then the edges of the newest growth are super dark, almost purple, then it goes back to normal colors?

the new growth is a lighter shade of green. Then midleaf it's purpleish in between the veins.

I don't understand these nutrients. But for sure things aren't quite right in yr garden. Are you supposed to use all those Nutrients together? And your pH ... this is a soil grow, yes? ... is low. Needs to be 6.3 - 6.5. Are you testing soil or testing runoff? Testing runoff is useless.

mega crop at 1.5ec
Bud explosion at .1ec
Sweet candy at . 1ec
Total ec 1.7

Micro nute def of some kind imo.. maybe lower the RH a bit..

RH is at 60%. Excuse the typo

Other than the problem mentioned above, plants look healthy

 

[ambertrichome]

I dont know, every time I see purple starting, that isn't genetic, I get suspicious of phytoplasma disease.
Its brought on by leafhoppers mainly.

 

[Dirrtybirdy]

I did a flush last night, but a day after the first pictures were taken the dark brown leaves turned to this. Hopefully the flush stopped the progress of this problem.

Anyone know what this could be?

 

[TanzanianMagic]

"In on day 2 of flower and I noticed this on some of my plants. I'm using 1.5 ec mega crop, .1ec sweet candy, .1ec bud explosion. Ph is at 6.0"

I just checked the Mega Crop Feeding Info, and their recommended EC is:

Veg 1 - Seedling/Small Plants: 0.55
Veg 2 - Normal Veg: 1.11
Veg 3 - Extended Veg: 1.25

Bloom/Flower Week 1-2: 1.39
Bloom/Flower Week 3-4: 1.53
Bloom/Flower Week 5-Harvest: 1.67

Source: https://greenleafnutrients.com/feeding-calculator/?v=796834e7a283

So the problem is that you're using 3x the recommended EC of nutrient concentration, considering these are small plants and should have an EC of 0.55, not 1.7.

 

[Dirrtybirdy]

I'm on week 1 day 5 of bloom. I've been feeding them 1.5ec for about 2 weeks now. Started showing the signs around day 2/3

 

[ambertrichome]

Looks like Tobacco Mosiac disease, or Phytoplasma/Witches broom.

Been around any tobacco, or notice any bugs.

 

[jackspratt61]

Looks like you wanted them someway.
Put 5 or 6 grams of good gypsum per gallon of water and give it them.

 

[jackspratt61]

Looks like you wanted them someway.
Put 5 or 6 grams of good gypsum per gallon of water and give it them.

Twanged

 

[SamsonsRiddle]

up your feeding to 3.0 ec and everything should get better. oh yeah, cal mag, too. you should get about a pound

 

[TanzanianMagic]

I'm on week 1 day 5 of bloom. I've been feeding them 1.5ec for about 2 weeks now. Started showing the signs around day 2/3

It is hard to see from the photographs how large the plants are. However I can still see the rockwool cubes they're in, so they're not even that far in 'normal veg' to quote their crop feeding info.

I don't even see any pre-flowers in the photographs.

--

If you want to try to salvage them, you should switch to the lowest nutrient concentration (0.55 EC), maybe a little (0.1 EC) extra P and K for root and stem development (say from a high P/K solution or flowering food - PK 13/14, Atami B'Cuzz 0-20-30, Ripen, etc.).

General advice

What you should focus on first is a large root system, thick stems/branches, and green leaves - phosphorus, potassium and magnesium. Keep the nitrogen low throughout the growth, until you need real growth in late flowering.

 

[Dirrtybirdy]

Looks like Tobacco Mosiac disease, or Phytoplasma/Witches broom.

Been around any tobacco, or notice any bugs.

have not been around any tobacco and have not seen any bugs. I searched pretty good and didn't see anything except a few fungus gnats.

Looks like you wanted them someway.
Put 5 or 6 grams of good gypsum per gallon of water and give it them.

up your feeding to 3.0 ec and everything should get better. oh yeah, cal mag, too. you should get about a pound

3.0 ec seems like a bit much for first week of flower.

It is hard to see from the photographs how large the plants are. However I can still see the rockwool cubes they're in, so they're not even that far in 'normal veg' to quote their crop feeding info.

I don't even see any pre-flowers in the photographs.

--

If you want to try to salvage them, you should switch to the lowest nutrient concentration (0.55 EC), maybe a little (0.1 EC) extra P and K for root and stem development (say from a high P/K solution or flowering food - PK 13/14, Atami B'Cuzz 0-20-30, Ripen, etc.).

General advice

What you should focus on first is a large root system, thick stems/branches, and green leaves - phosphorus, potassium and magnesium. Keep the nitrogen low throughout the growth, until you need real growth in late flowering.

Plants are about 2.5ft tall. I lollipopped them before I flipped them then supercropped them. I'm on the first week of flower so no preflower development yet. There is good root development. Had a good veg and no signs of any deficiencies. It happened 2 days after flipping them.

Not really sure what's going on...

 

[f-e]

How do the roots look? Shabby I'm guessing.

I have no idea what megacrop is, but it sounds like Dollar store stuff. Has anyone ever done a good grow with it?

I would mix a standard bloom feed at around 1.3 looking at them. Water them till runoff. Gather that first bit for testing, and expect something off the clock. Then put another liter of that basic 1.3 bloom feed through each of them. No additives. Just correct the pH.

The good thing about your inert medium is that you can totally exchange the food content by just jugging them through. Don't drip it in, jug it evenly over the surface. Sliding the plastic wrapper up half inch can be useful, to contain the water as you jug them.

Confirm your testers work correctly, before doing any of this. Or your just pissing in the wind.


Unless using led's or co2, you're unlikely to ever want 1.7

Boosters are a great way of emptying your wallet. As a newb, stick to just feed. Then progress to PK boosters. When you can actually see they could benefit from it. Living on the cusp of a deficiency showing, is better for your smoke, than too much feed. We should try to feed as little as possible, and then we will see signs of just what could be lacking. N being very common, and PK as they are the main requirements. Calcium and Magnesium pop up a lot. Anything else is probably a fuck up. Just wash it all away, replacing it with something known to be good. Which at this stage, is simply a working flower feed.

Out of interest, when I boost with PK, I don't just add it as an extra. I might drop my base from 1.3 down to 1.2 and then use the PK to increase to 1.4 So my feed is little stronger, but proportionally it's better for say week 5. You are doing what we all probably did. Running everything at maximum, except for the plants, which are suffering because of it. That 1.5 might be maximum, but with co2 and LED's which you likely don't have. My suggestion of 1.3 might be too high. But we have to start somewhere.


Sorry to be repeating a lot of what others have already said. They are just so damn good, there was nothing new left

 

[TanzanianMagic]

Plants are about 2.5ft tall. I lollipopped them before I flipped them then supercropped them. I'm on the first week of flower so no preflower development yet.

2.5 feet is the definition of small plants, no mattter whether you flipped the light schedule. You should treat them as if they're still in early veg, then slowly raise the EC if you see deficiencies.

It is better to underfeed them for a little while, than to nuke them, which is what happened.

 

[greenspiritz]

Boron Deficiency.

Flush 3x the pot volume with water, then after that flush, add just your standard bloom nutrient at an EC 1.2, no additives or supplements.

Keep PH 6.2 - 6.5

Get some formulex by growth technology and use 2.5ml a litre and spray once a day for 3 days first thing when the lights come on, then spray every 3 days till it improves.

Keep the EC 1.2 till week 3. Then up EC 0.1 every 5 - 7 days.

Keep temperature 18c night - 28c day

Humidity 40% - 60%

Allow the soil to dry before each watering

 

[TanzanianMagic]

Boron Deficiency.

Even if it is specifically boron lockout, what causes that?

https://www.royalqueenseeds.com/blog-boron-deficiency-in-cannabis-plants-n604

PREVENTION
To help prevent a boron deficiency:

Make sure plants do not dry out too often.
Don't over-fertilise! This will cause nutrient lockout.
Make sure the humidity is above 25%. A humidifier or dehumidifier is always a good idea when growing indoors.
Always use cannabis-specific nutrients with the necessary cross-section of elements.
Soil growers should use a comprehensive, well drained soil.

So it's back to overfertilization.