Is that overfert?

[gigi86]

Hi my plants are around at 40 days flowering time but 1 week ago some of those start to have some yellow in the older leaves and curl over with burn sign.
water half ro half tap EC 0.3
I m feeding once a day with canna coco a\b 1ml per 1\4 gallon now before it was coco a\b 1,5ml per 1\4 gallon + pk 2ml per gallon and cannazym , bloom boster.
I already flush whit plain water ph5.8 and final water with a bit of nutes EC 0.7 for eventually salt build up

Atm those are the best pics I can take =( I will update tomorrow

 

[jackiee]

hi gigi86,your nutrients seem to low to me as i like to keep ph 5.8 and ec 1.6 or as close as possible.at 40 days flower, your plants should be putting some serious gain on,but only if theres eneough fertiliser to allow them to hope this helps.stay lucky

 

[gigi86]

So you think I need to give more nutes and there is no overfert or salt sign? I hope you right man I try to rise up EC to 1,6 slowly today I will feed them with EC 1,2 coco a\b +pk13\14+bloom boster.
I also have bio nova mg 8% but If that is not a mg deficiency I will dont need this for now....

 

[SeaMaiden]

Check for flyers that resemble fungus gnats. If you find them, you need to tear into one of the rootballs of the affected plants and look for tiny bugs that resemble ticks or aphids. These would likely be root aphids and if that's what you've got, it's neither over nor under fertilization. You'll need to work very hard to nurse a crop out of them if they do have RAs, too.

Those plants don't look exactly over or underfertilized, and that, along with the fact that they're around week 3 of flower suggests all too strongly to me that you may very well have root aphids.

 

[Snow Crash]

I think the PK13/14 is tossing your chemistry here.

At 5ml per gallon of A and B you're working with not much more than 23ppm of Phosphorus.

The addition of 2ml of PK13/14 is now contributing another 23ppm or so, basically doubling the presence of that element in your solution but not to some extreme level. 46ppm of P, or so, is completely within reason. I am not certain that the ppm level of Phosphorus is the issue as much as the source might be.

In addition to the nutrient change that has coincided with your issue I would guess that temperatures in your grow space have been a little difficult to control. If it can be managed then I'd be doing everything I could to keep my temperatures under 76 degrees for the remainder of the grow.

Rinsing the media with clean water is a terrible idea. Coco washes out different elements at different rates and you could be causing your own imbalances. When I need to rinse out salts I will use a 1/2 strength solution (same ml of nutrients, twice as much water) and I will collect a large amount of runoff. To really rebalance coco I find that as much as 2 gallons of solution must be collected for every gallon of media.

Since you have an EC meter yourself you can check if the salinity of the media is too high by testing the runoff. Collect at least 2 Liters of runoff for testing to get a good sample. If the runoff is >130% of the feeding solution (like, 1.0ec in and more than 1.3ec out) then you have a buildup of some elements. I would suggest rinsing the media with a 1/2 strength solution then. I would also encourage you to increase the volume of runoff you are collecting and to discontinue the clean water flush until the end of the grow when you REALLY want to flush it out.

The dead leaf mass is little more than crunchy food for pests and a place for mold to get a foot hold in. You can remove all of the necrotic leaf tissue without stressing the plant (like cutting off a frostbitten toe) but make sure to leave all the green leaf mass intact. One thing that seems to help with plants like this is a gentle foliar feed of 1/4tsp of Epsom Salt per liter. Apply this to the back side of the leaves just as the lights come on. The Mg and the Su will both help your plant maintain the remaining healthy chlorophyll.

 

[praisehim.]

the plants furthest from the light look healthier. ur leaves are curling upwards, and your nute regiment is fine.

and yet, no one's asking about temps...

check your temps and airflow, those plants look heat stressed. the light may be to close...

 

[gigi86]

tnx all guys for the answer
For snowcrash : now I know that in coco medium I need to flush with half strenght nutes ( now I see after the wash the burn It's going to other leaves) , so I think I will nedd to flush with EC 1 without adding pk just canna coco and ph down.
My growroom temperature is : min 19° max 28°
Today I feed it with EC 1.5 ( coco a\b 12ml each + pk 6ml in 7 litres of water) just to see if tomorrow the baby will looking happy.....

this is today situation :

 

[gigi86]

Today I watch my room temperature and was max 28 min 15.....
I also saw that my pot still heavy and wet after 2 days without water.... so I m start to think that maybe is a overwater that cause this to the older leaves , I will try to w8 the pot be a bit dry on the top and give just less water a day like 1 L per pot (12L) .

 

[Granger2]

gigi,
Nice dog. I fear for his/her eyesight under HIDs. SeaMaiden may well be right. I'm battling root aphids now, but I'm stuck in veg till I make some headway.

I've done a fair amount of research on the forums and web. ICMag has a root aphid thread. People on that thread have used all kinds of insecticides including things like systemics that I don't want to smoke. What it boils down to is that the most effective tool is to water them with beneficial nematodes. The same ones you buy to spray your yard for fleas, ticks, etc. They will lay their eggs inside any ground dwelling pest. The eggs hatch, eat the pests insides, then emerge to lay more eggs.

They persist in the soil and can survive ferts. I ran across a very cool magnified photo of dead root aphids laying there with holes blasted out their abdomens. Alien vs. Predator.

The beneficial nematodes come in a sponge. You stir and ring out the sponge in a gallon of water to make a concentrate, and simply water your plants with it.

I would suggest hand watering them regardless of what system you use. They're cheap, and I'd advise you to get the root aphids under control because they will be persistent in your grow room otherwise. The nematodes are effective on fungus gnats, and other pests in the medium. I will, in the future, routinely treat all my crops with nematodes. Good luck. -granger

 

[zor]

looks like aphid damage to me as well.

 

[gigi86]

today I will chek root and hope to dont find it

 

[gigi86]

Hi guys I have check the root and havent see anything move just see the root was not too white a bit darker than white maybe is this the problem....

 

[stagafolaysa]

i had similar issues in my last grow. I also think it was the pk addition. I did seem to have something to do with exposure to light. maybe it was both combined. But then, I also had fungus gnats. I don't think it was the gnats.

 

[SeaMaiden]

Based on your second set of pix in more natural lighting, I agree with whoever said the plants may be light-burned.

 

[indalo]

Had the same problem if the PK 13/14 is the reason. Once all the leaves have dried out , it spreads to the buds , completly drying them out. Ruined my crop. Loads of growers are against using it, me included.

 

[gigi86]

there are 3 possible reason:
1 light burn
2 salt build up or overwater
3 root rot
the n1 is what I think at first but after some middle leaves yellow too I start to suspect other cause like n2 , so I flush with plain water ( and this is my fault) and after I feed it again with Ec 1.4 .....
Now I feed with half strenght and without pk only coco a\b EC 1-1.2 once every two days.
Today I check the leaves and seem a bit better so maybe this is the right way....

 

[Snow Crash]

1. No such thing as "light burn." Maybe if there were crimps in your reflector and the burns were localized (like as it would be with a magnifying glass). Light doesn't burn chlorophyll, the inability to mobilize the energy generated by the chlorophyll will cause them to burn themselves up. Magnesium is crucial for the mobility of generated energy within the plant for growth.

2. Have you bothered checking your runoff EC yet? One test and you would know for certain if you have build up.

3. Overwatering is doubtful given the size of the plant and the media, although if you transplanted somewhat recently and the root ball has not had a chance to grow then you could be stunting new root growth. After transplants I allow for longer periods of time between waterings.

4. Root Rot would go along with an overwatering issue. Technically, overwatering isn't the problem... It's the damage that overwatering does to the root system that's the problem. Kind of like how a virus doesn't give you brain damage, but if your body runs a temperature over 106 for too long you will get brain damage. The problem is complex because it involves a complex system that depends on balance.

The long and the short of it is your plant is out of balance. So... Check the balance of the EC. Allow for a greater balance of wet/dry. And perhaps you should begin using a root supplement (I prefer Root's Organics BioRoot and BioWeed) to help encourage new root growth. Whenever a plant is sick it's usually because the "rules" aren't being followed. You have all the testing equipment you need to discern what the cause of the visible problems are.

Check your runoff EC!!!

If you're feeding 1.4 ec and the runoff is over 1.8ec then you know that the media likely has a higher charge than 1.8ec, which is probably the source of the issue.

If the runoff is under 1.8ec then your problem is with your root zone. Dedicate time and energy to building more roots and this will help resolve the issue.

Also, leafs don't heal themselves. What is dead is dead. Look for signs that the problem is slowing or not progressing to new/healthy growth. If the problem is not progressing then your issue was temporary and to apply a resolution to a problem that no longer exists will only cause more headaches for you.

Test your runoff EC!!!

Did I make that clear?

 

[gigi86]

Tnx snowcrash for help now its more clear what I have to do , today I will check run off EC

 

[praisehim.]

light burn doesnt exist ? no shit. they probably meant heat stress, which for some reason has not been dealt with.
you've over watered and its too hot. ppl say you cant overwater in coco, but its bullshit.
handle those two before even thinking about looking at the food you are giving.

room efficiency is key to growing good herb, not the nutes.

 

[gigi86]

I have check EC of runoff :
EC in 1.2
EC out 1.4
PH 5.8 in
PH 5.8 out
For praisehim I m using sputnik reflector and I set the hps about 40 cm from the highest bud and I think too that overwater in coco is possible because when I was using drip system in coco I always overwater the baby in particulary after transplant.
Some leaf still going to dye and now I saw some bud that stopped ( never seen before) .
I will never give up ;D