2nd grow fails because of yellowing week 3-4 flower

Infested Herb

New Member
Hello,

My name is Hugo and I'm looking forward to the day when I'll be smoking my own good quality cannabis, BUT I still have a lot to learn and I have a problem that I can't solve and i'm getting really frustrated. I It's the second time my 6 plants start to yellow at 3-4 weeks into bloom and when i change my light from MH (bright white light for the eye) to HPS (a lot more yellow looking light for the eye).

Gear

Grow tent: 100x100x180cm (40x40x70 inch)
Square 11L (2,9 Gallon) pots 22x22x26cm
Grow lamp MH 600 Watt Sonlight - Veg
Grow lamp HPS 600 Watt Sonlight - Bloom
Sonlight Digital Ballast 4D (Dimmer 250 / 400 / 600W / SL (Super Lumens)
LONG-GLOSS 50 V reflector
Carbon Filter: Prima Klima - Filter ECO line ø10cm - max 240m3/h
Extractor: Blauberg BI-Turbo ø10 cm - 187m3/h

Nutrients

Canna PH- (min) Grow 1 liter
Canna ph- (min) Bloom 1 liter
Canna PH+ (5%) 1 liter
Canna Terra Vega 1 liter
Canna Terra Flores 1 liter
Canna Rhizotonic 500ml
CannaZym 500 ml
CannaBoost Accelerator 250ml
Canna Cure 750ml (handspray)

Soil

Canna Seed Mix 25ltr
Canna Terra Professional 50 liter
Canna Terra professional plus 50 Liter

My first grow plants died due to the same problem that occurs now. Yellowing of all the fan leaves, then spreading. I don't think the problem is pH because I grow in soil giving water at pH:6-6,5-7 variating every time. Don't think it's nitrogen defiency because I had an nitrogen burn in veg and flushed them all and giving them low to medium quantity of CANNA bloom nutrients. I did have spider mites, but got rid of them with Canna Cure spray and BAC Plant vitality plus. I changed my light from MH to HPS (both 400 Watt), and the yellowing started. I find it hard to believe it has anything to do with the lighting but I'm getting desperate here.

Pictures coming later this day.

Thank you :420:
 
Lights are off,
22047662_10207293871423314_1128460766_o.jpg
 
Hey there man, sorry no one has responded to you yet, lets give this a bump nd help the guy out.
Some of the plants look quite droopy, could you telk us how often you are watering them?
Anyone have any ideas?
I know iron deff can cause upper and inner leaves to go yellow/white , not sure though.
All the best man.
Peace ✌
 
The symptom looks like nitrogen DEF but why. I think you need to go up and down your plants with a fine tooth comb because I think you have pests. Your top leaves which aren't as effected look like they have mite/thrip damage. You could also have some pests munching roots as well.
 
Check your water runoff PH and PPM. Every plant I’ve ever grown in soil does this to me. When I checked my runoff i had salinities of 3000ppm and ph of 4.5. I had terrible luck with soil. I never watered to runoff though and my soil always became toxic. I used many of the brand name organic soils out there with the same results. Watering to runoff helped but then I starved them as I didn’t fertilize much. I’ve finally switched to coco and haven’t had a single deficient leaf in 2years.

Don’t scrap those plants. They’ll finish fine. A good flush followed by basic fertilizer treatment will carry you through. Keep us posted
 
This might help

cannabis_nutrient_deficiency-chart_C.jpg
 
The symptom looks like nitrogen DEF but why. I think you need to go up and down your plants with a fine tooth comb because I think you have pests. Your top leaves which aren't as effected look like they have mite/thrip damage. You could also have some pests munching roots as well.

Thank you for responding MrCanada!

It is probably a nitrogen DEF, they had an overdose of nitrogen for about 2-3 weeks in veg, flushed them after 1 week and it got better, but it slowed them down a lot. I did have mites, I ordered BAC Plant vitality Plus 250 ml and Canna cure, the delivery took very long (2weeks), that didn't help too. I sprayed 2x Canna cure on the plants and 1x BAC, 4 days between each, but the damage that had been dealt was already to much. The root rot is probably there too, they were really droopy 1 time (see picture!), and that could cause that I guess?
 
First of all, thank you all for responding, very much appreciated!

I normally water my plants every 3-4 days. I'll just feel if the top inch of the soil is dry then i'll water my plants till I see some runoff water. It takes about 2-3 liters (0.5-0,79 US gallons) to get runoff water afterwards the soil will stay wet for 3-4 days. I don't know if I should water my plants with nutrients everytime, I watered them without-with-without-with nutrients. They recommend 4-7 ml (0,13-0,27 US fluid ounces) per liter (per 33,8 US fluid ounces), But I only gave 1-2 ml felt like it would have been to much, could be wrong though. After the yellowing started, I was a bit frustrated so I gave 4ml/Liter, as expected it didn't help, one plant showed signs of nutrient burn so now I'm ony giving them water without nutrients. I feel like the plant doesn't even need the nutrients cause of all the leaves that died/are dying, the plant can't even consume the nutrients. Afraid of flushing cause the soil won't even dry since there are no/few leaves left, Should I?

Sadly I don't have a ppm meter, because they are pretty expensive, but I feel like I really should get one tho...

I'll post pictures of what they look like right now 5 October 00:44 AM, and i'll post pictures of end result.
 
Looks like sulphur deficiency, sprinkling a few handfulls of garden gypsum to your pots before watering will add Sulphur and calcium without affecting pH.
Sulphur deficiency will show purple streaks along the main stem and light colored top fan leaves that progress downwards.

Thank you for responding Luweedgi

I'm not so familiar with garden gypsum, where can I buy them online? I live in Europe so can't order it on Amazon... Thank you for the information!
 
Check your water runoff PH and PPM. Every plant I've ever grown in soil does this to me. When I checked my runoff i had salinities of 3000ppm and ph of 4.5. I had terrible luck with soil. I never watered to runoff though and my soil always became toxic. I used many of the brand name organic soils out there with the same results. Watering to runoff helped but then I starved them as I didn't fertilize much. I've finally switched to coco and haven't had a single deficient leaf in 2years.

Don't scrap those plants. They'll finish fine. A good flush followed by basic fertilizer treatment will carry you through. Keep us posted

Thank you for the response Spitz!

I think my runoff PH is fine, I will check it tomorrow or the day after, always watered with 6-7 pH water. I was even considering to grow with coco, but figured I should learn how to do it proparly with soil, since it's the 'easiest' ^^. How did they look when you starved them? I'm also afraid of giving to much nutrients every watering. Probably trying coco next time. Trying my best to 'save' them while I still can, not so sure if I should flush because they have no or few leaves left, (afraid that the soil won't dry and it might get worse). Think they only need/have 1-2 weeks and it will be done.
 
First of all, thank you all for responding, very much appreciated!

I normally water my plants every 3-4 days. I'll just feel if the top inch of the soil is dry then i'll water my plants till I see some runoff water. It takes about 2-3 liters (0.5-0,79 US gallons) to get runoff water afterwards the soil will stay wet for 3-4 days. I don't know if I should water my plants with nutrients everytime, I watered them without-with-without-with nutrients. They recommend 4-7 ml (0,13-0,27 US fluid ounces) per liter (per 33,8 US fluid ounces), But I only gave 1-2 ml felt like it would have been to much, could be wrong though. After the yellowing started, I was a bit frustrated so I gave 4ml/Liter, as expected it didn't help, one plant showed signs of nutrient burn so now I'm ony giving them water without nutrients. I feel like the plant doesn't even need the nutrients cause of all the leaves that died/are dying, the plant can't even consume the nutrients. Afraid of flushing cause the soil won't even dry since there are no/few leaves left, Should I?

Sadly I don't have a ppm meter, because they are pretty expensive, but I feel like I really should get one tho...

I'll post pictures of what they look like right now 5 October 00:44 AM, and i'll post pictures of end result.
Herb, ppm pens are fairly cheap. Less than $20 for what you need. Well worth the investment.
 
It's going to be tough to pinpoint which problems are what until the pests are for sure gone. I had a PH issue mid flower and flushed and got those pale leaves as well
 
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