Burnt and yellow leaves

Latino-grower · Oct 10, 2018

Hey guys, my plants are having some trouble and I'm accepting advices... So, they are at the 6th week of flowering and, since about two weeks ago, they started to present some problems.
At first, I thought it was light burn or too much heat, as the lights of the grow were replaced three weeks ago, from 210W CFL lights to a 250W HPS (31k lumens) one, without cooltube and, at first, the yellow and burnt leaves were only the ones receiving direct light. The HPS light was placed around 30 to 35 centimeters from the canopy, but, a week ago, I moved the light to about 40 cm from the canopy, and the problem persists, even affecting leaves that are not directly under the lights...
Then, I increased the Mg on the weekly dose of ferts, imagining that it could be a Mg deficiency, but that didn't did the trick. I also tried to flush them with 6.5 ph water, to no effect (it was not a proper flush, though). After all that, the leaves are still slowly being affected by this problem and the buds are not getting fat in a satisfactory manner.
The plants (a Somango and a Super Silver Haze) are being fertilized weekly with BioBizz - Bloom, 10ml; Grow. 6ml; and Alg-a-Mic, 6ml - and Magnesium Sulphate - two teaspoons. Any ideas?

Super Silver Haze, the least affected oned (sorry for the lying down pictures)

Somango

red23 · Oct 11, 2018

Latino-grower said:
Hey guys, my plants are having some trouble and I'm accepting advices... So, they are at the 6th week of flowering and, since about two weeks ago, they started to present some problems.
At first, I thought it was light burn or too much heat, as the lights of the grow were replaced three weeks ago, from 210W CFL lights to a 250W HPS (31k lumens) one, without cooltube and, at first, the yellow and burnt leaves were only the ones receiving direct light. The HPS light was placed around 30 to 35 centimeters from the canopy, but, a week ago, I moved the light to about 40 cm from the canopy, and the problem persists, even affecting leaves that are not directly under the lights...
Then, I increased the Mg on the weekly dose of ferts, imagining that it could be a Mg deficiency, but that didn't did the trick. I also tried to flush them with 6.5 ph water, to no effect (it was not a proper flush, though). After all that, the leaves are still slowly being affected by this problem and the buds are not getting fat in a satisfactory manner.
The plants (a Somango and a Super Silver Haze) are being fertilized weekly with BioBizz - Bloom, 10ml; Grow. 6ml; and Alg-a-Mic, 6ml - and Magnesium Sulphate - two teaspoons. Any ideas?

[URL=https://www.icmag.com/ic/picture.php?albumid=78340&pictureid=1890775&thumb=1]View Image[/url]
Super Silver Haze, the least affected oned (sorry for the lying down pictures)

[URL=https://www.icmag.com/ic/picture.php?albumid=78340&pictureid=1890774&thumb=1]View Image[/url]
Somango

Hi there

I think it must have all started with a leaf burn,and was translated later on as a deficiency of some sort.
I've been using BioBizz Bloom and TopMax only,at flowering stage,with exceptional results.
After flashing,I would have given the girls, just water for a few days, then 1/2 the amount in ml(Bloom/TopMax),to eliminate possible "lockdown" you might have accidentally caused.
I think its a combination of the two, light change a bit, but it all started with a burn that progressed in a "lockdown".That's why growth has slowed down.
It might help
Best of luck anyway(hope you have checked for mites etc)

Latino-grower · Oct 12, 2018

red23 said:
Hi there I think it must have all started with a leaf burn,and was translated later on as a deficiency of some sort.
I've been using BioBizz Bloom and TopMax only,at flowering stage,with exceptional results.
After flashing,I would have given the girls, just water for a few days, then 1/2 the amount in ml(Bloom/TopMax),to eliminate possible "lockdown" you might have accidentally caused.
I think its a combination of the two, light change a bit, but it all started with a burn that progressed in a "lockdown".That's why growth has slowed down.
It might help
Best of luck anyway(hope you have checked for mites etc)

Red23, thanks for your help! The last time I gave ferts to the plants was last week, on monday. Do you think I should skip fertilization this week and flush the plants again, this time with more water? I only used 3.5 liters of water to each plant on my last flush, which was on the last saturday (I'm using 7 l. fabric pots).

red23 · Oct 13, 2018

Latino-grower said:
Red23, thanks for your help! The last time I gave ferts to the plants was last week, on monday. Do you think I should skip fertilization this week and flush the plants again, this time with more water? I only used 3.5 liters of water to each plant on my last flush, which was on the last saturday (I'm using 7 l. fabric pots).

If since Monday,you haven't seen any significant(in your eyes)change,fllash her one more time.She won't mind.I feel that most probable cause for the latest yellowing, is "lockdown" due to excess nutrients in her diet.At the same time, you are aware some fan leaves will yellow when they are reaching the end of flowering.Do it when she is done with her day time circle, let her "sleep" after flashing.I always water, defoliate,feed etc plants when they are done with the lights.If there's something they don't like,it normally shows the morning after.
Burnt leaves beyond repair,I would cut them off.
Give her a few days on water, come back, with a photo if you can,and,then lets see what the leaves are saying.Temp. around 28C,humidity around 50%
P.S when flashing, water has to come out as clear as it goes in, if you get my meaning.All nutes out.

Latino-grower · Oct 13, 2018

red23 said:
If since Monday,you haven't seen any significant(in your eyes)change,fllash her one more time.She won't mind.I feel that most probable cause for the latest yellowing, is "lockdown" due to excess nutrients in her diet.At the same time, you are aware some fan leaves will yellow when they are reaching the end of flowering.Do it when she is done with her day time circle, let her "sleep" after flashing.I always water, defoliate,feed etc plants when they are done with the lights.If there's something they don't like,it normally shows the morning after.
Burnt leaves beyond repair,I would cut them off.
Give her a few days on water, come back, with a photo if you can,and,then lets see what the leaves are saying.Temp. around 28C,humidity around 50%
P.S when flashing, water has to come out as clear as it goes in, if you get my meaning.All nutes out.

Thanks again man, your lockdown theory makes sense, I think I went a little bit too far with the ferts... The plants day cycle is almost ending, I'll flush them again and hope for some improvements. Cheers!

red23 · Oct 13, 2018

Latino-grower said:
Thanks again man, your lockdown theory makes sense, I think I went a little bit too far with the ferts... The plants day cycle is almost ending, I'll flush them again and hope for some improvements. Cheers!

LG no problem.A question.
What's the flowering time for the girls, as described by the breeder?

Latino-grower · Oct 13, 2018

red23 said:
LG no problem.A question.
What's the flowering time for the girls, as described by the breeder?

red23, I wasn't able to get the specific info from the breeder, as it's a very small one (Santa Semilla, from Chile), but acording to leafly, it's 10-11 weeks for the Super Silver Haze and 9-10 weeks to the Somango.

CrushnYuba · Oct 13, 2018

Hmm.. Have you been using these fertilizers for a while? What's your soil like? Are there nutrients in your soil? Is it amended?
I don't think you went to far with the macro nutrients. That stuff is 1-2-2 for bloom. That's really weak. i have a free sample bottle of bio bizz and i think i will just pour that bottle undiluted into the soil on 1 plant.
Kind of looks like a potassium deficiency. Epsom salt can be tricky to use. Why do you supplement magnesium and not calcium? And whyyyy 2 tsp of Epsom? That's an insane amount. It's a micro nutrient
Maybe I'm misunderstanding something but it seems like you are giving your plants more mag then n p and k.
10ml of Epsom at 10% mg
10ml of bloom at 1%n 2%p 2%k

red23 · Oct 13, 2018

Latino-grower said:
red23, I wasn't able to get the specific info from the breeder, as it's a very small one (Santa Semilla, from Chile), but acording to leafly, it's 10-11 weeks for the Super Silver Haze and 9-10 weeks to the Somango.

Cheers.See how thing go,and,in about 2/3 weeks, you need to start contemplating reducing ferts,flashing(final),for the Super Silver Haze at least.

Latino-grower · Oct 14, 2018

CrushnYuba said:
Hmm.. Have you been using these fertilizers for a while? What's your soil like? Are there nutrients in your soil? Is it amended?
I don't think you went to far with the macro nutrients. That stuff is 1-2-2 for bloom. That's really weak. i have a free sample bottle of bio bizz and i think i will just pour that bottle undiluted into the soil on 1 plant.
Kind of looks like a potassium deficiency. Epsom salt can be tricky to use. Why do you supplement magnesium and not calcium? And whyyyy 2 tsp of Epsom? That's an insane amount. It's a micro nutrient
Maybe I'm misunderstanding something but it seems like you are giving your plants more mag then n p and k.
10ml of Epsom at 10% mg
10ml of bloom at 1%n 2%p 2%k

Man, thats the 3rd time I use BioBizz, and before I never had any big problems like I'm having this time.

My soil is half spaghnum peat moss and half perlite, and I had a rootbound problem with this plants earlier, during veg (they are incredibly delayed, I planted them on april).

The plants were receiving those amounts of ferts on 3-4 liters of water. Apparently, I was suposed to water them, wait a little, and then give only 1 liter of water to both of them with the amounts of ferts indicated on BioBizz charts, which are about 1/3 of what I'm giving to them. Also, I already tried to increase potassium to counter a possible deficiency with no results. Maybe it is actually a potassium deficiency, but due to the lockdown on the soil.

Regarding the Mg, I don't think I'm giving them too much, according to what I see people doing... What do you think an adequate dose is?

BTW, thanks for the inputs.

red23 said:
Cheers.See how thing go,and,in about 2/3 weeks, you need to start contemplating reducing ferts,flashing(final),for the Super Silver Haze at least.

Sure, I already flushed them, this time with 14 liters of water to each, though I'm not seeing any big differences until now... I think tomorrow I will start with the ferts again, but this time in a smaller dosage. Hope they build up more weight until harvest time. Later I will update here with some current pictures.

CrushnYuba · Oct 14, 2018

You have to do your fertalizer per gallon of water or per liter. Not total amount given.
I think in gallons. 4 liters is only one gallon. It's not that 10ml of epsom on a plant that needs magnesium is to much... But every week seems like to much. it's not balanced with your other fertalizer. It's a micro nutrient and you are giving the plant more mag then macro nutrients.

Latino-grower · Oct 14, 2018

CrushnYuba said:
You have to do your fertalizer per gallon of water or per liter. Not total amount given.
I think in gallons. 4 liters is only one gallon. It's not that 10ml of epsom on a plant that needs magnesium is to much... But every week seems like to much. it's not balanced with your other fertalizer. It's a micro nutrient and you are giving the plant more mag then macro nutrients.

CrushnYuba, I was actually mixing 2 teaspoons of Sulphate Magnesium (Epsom Salt) per gallon. The amounts that I mentioned in my post (Bloom, 10ml; Grow. 6ml; Alg-a-Mic, 6ml; and Magnesium Sulphat, two teaspoons) were being mixed in a gallon of water and then applied in the plants, about half gallon of that mix to each one, tough I always gave a little more to the Super Silver Haze, as it is a lot bigger than the Somango.

Latino-grower · Oct 15, 2018

So, here are some pictures from tonight

red23 · Oct 15, 2018

Latino-grower said:
So, here are some pictures from tonight

Hi.Free standing in a corner and no reflective film for those two walls?(please correct me if I'm wrong)However much you turn, spin,move up and down the two girls,I think you have light penetration issues.If that's the case, defoliation,apart from your other actions, is a must.

Latino-grower · Oct 15, 2018

red23 said:
Hi.Free standing in a corner and no reflective film for those two walls?(please correct me if I'm wrong)However much you turn, spin,move up and down the two girls,I think you have light penetration issues.If that's the case, defoliation,apart from your other actions, is a must.

Hey red23, There is no reflective film on the walls (you mean something like mylar, right?), but they're already covered in a kind of reflective paint. I didn't understand the part of the "free standing"... When you mention ligh penetration issues, you mean that the bottom part of the plants is not getting enough light? That would be strang, as I changed my regular 210W CFL lights to a 250W HPS one at the beginning of the flowering stage. Also, isn't it too late to defoliate the plant in order to stimulate the buds? I read that people usually do this up to the 3rd week of flowering, and I'm already on week 7. Cheers,

red23 · Oct 15, 2018

Latino-grower said:
Hey red23, There is no reflective film on the walls (you mean something like mylar, right?), but they're already covered in a kind of reflective paint. I didn't understand the part of the "free standing"... When you mention ligh penetration issues, you mean that the bottom part of the plants is not getting enough light? That would be strang, as I changed my regular 210W CFL lights to a 250W HPS one at the beginning of the flowering stage. Also, isn't it too late to defoliate the plant in order to stimulate the buds? I read that people usually do this up to the 3rd week of flowering, and I'm already on week 7. Cheers,

I am more concerned with the short/bushy one,and,not so much with SSH which seems to be doing much better like you said.Bushy/short ones need to be trimmed, quite often so you get light penetrating through the plant from top to bottom.Wall paint, reflective?,not enough for those kind of strains.
According to this chart, with the short one, you have at least a build up of Nitrogen,late stage, caused by not starting defoliating(leaves need light) at an earlier stage,and, persisting with overfeeding her.
A plant has a root and leaves
If it was my plant(as she stands at your place), after flashing,I would definitely defoliate worst affected fan leaves, stop the ferts,get the new exposed leaves and root system find their way to work harmonious again together for the next few days,with just water
I would at the same time forget about quantity, and,try and get some quality into the equation.
Apart from all that, buds look nicely developed

CrushnYuba · Oct 15, 2018

2 teaspoons is 10ml. Epsom salt is 10% magnesium by weight! Look at the 3 npk numbersof your main ferts. That is what their percentage is by weight.
That weak bio biz stuff doesn't have any numbers close to 10%. Exactly what are the numbers listed on the bottle as 0-0-0? I see conflicting numbers for those products online but all numbers i have seen are pretty weak. You are doing 10ml of bloom at an n-p-k of ? And 6ml of grow at an npk of? I bet u got more mag them your macro nutes.

Your n p and k are your main nutrients. Mag is a micro. It rarely even really needs to be supplemented. Allot of Times you get enough just from the lime in Your soil and your water. Calcium is the micro you need the most of And i don't even know where you are getting that from.

Also, when you feed small pots, you should be completely saturating the soil until you get run off coming out of the bottom. It seems like you are not doing that. You are giving one plant more then another. U are getting salt build up from your epsom SALT and it's burning.

Absolem · Oct 15, 2018

Calcium and magnesium are macro nutrients.

CrushnYuba · Oct 15, 2018

I stand corrected. I guess they can be considered "secondary macro" nutrients. Either way, it's a problem if your plants are getting more magnesium and sulfer then n p k and calcium. Especially in salt form. And Especially not getting any run off

I don't know why no one is chiming in to say this is not right.

Absolem · Oct 16, 2018

CrushnYuba said:
I stand corrected. I guess they can be considered "secondary macro" nutrients. Either way, it's a problem if your plants are getting more magnesium and sulfer then n p k and calcium. Especially in salt form. And Especially not getting any run off

I don't know why no one is chiming in to say this is not right.

It's a tough fix.

All liquid ferts are made from salts. But I do think they are adding to much Epsom.

Hey Latino

Just a few observations.

You grow in 7 liter pots close to 2 gallons. 50% of that is perlite which means only 1 gallon of your pot is used to bind nutrients to the peat then the plant feeds off the stored nutrients in the peat and whats in the nutrient solution contained in the pot that isn't bound to the peat.

Lets say you have 100 spaces in your peat that need to be filled before the peat can deliver food to the plants. These spaces are filled with K Ca Mg some Fe. If the 100 isn't filled the plant doesn't eat as good. It's called a buffer and keeps the plant from being overfed. Now if the 100 spaces aren't filled then the plant looks overfed because it is feeding heavily on N and P because that is what's most available to the plant.

"Flushing" washes the buffer out of the peat. Not good unless the plants have been heavily fed and your's haven't.

Things may have gone good before because the roots may have been smaller? Causing the low feed to be enough. With a plant that has a nice root ball it can eat like a hog.

The amount of perlite added to the peat increases the available N to the plant and decrease the amount of K Ca Mg.

My only two suggestions,
1. Decrease the perlite to 25% to get a better balance of feed to your plants.
2. Make sure your roots fully fill the final pot they are in.

A pot with a nice root ball and the buffer filled in the peat can be fed almost every watering. When the peat needs to be watered. Feed when the pot is 50-60% saturated. A weak or small root system in a pot makes the plant very temperamental.

Peace.

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