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Burnt and yellow leaves

Latino-grower

New member
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

Hey red23, I still don't think the problem is light penetration... I had plants with this size before with 210W CFL lights, and never had such complications. I don't see how they can happen now, when I have a HPS that has more wattage and light penetration power. Despite that, I decided to cut some the affected fan leaves that were getting in the way of the buds, hope this will help them get some weight... Thanks again for the advices!

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.

ChrushYuba, thanks for your comments.

Here are the numbers from my BioBizz ferts: Grow, 3 - 0 - 8; Bloom, 1 - 2 - 2; and Alg-A-Mic, 0.1 - 0 - 0.2.

I did some further research and the dosage of Epsom I'm using do seems a bit high according to some people, though I still see lots of reports were people use this exact dose, or even more, with good results. Besides that, it is very difficult to overdo with Epsom, as it is "washed" easily from the plants. I also always let some run off when watering/fertilizing the plants.

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.

Absolem, thanks for your input, it was very enlightening! I will research more about this "buffer" effect.

The biggest problem I had with those plants,which is definetly contributing to the current situation, was the roots system. I didn't knew the importance of stimulating the root system in order to create a proper root ball, so I just transplanted those plants from 500ml cups to 7L pots. As a result, the plants became rootbounded. I even try to prune the Somango roots, but it actually made things worse, which is clear when you compare then to the SSH, that wasn't pruned.

I never spent so much money with a grow with such disappointing results. I think I will harvest less than in my last one, that was in a smaller grow and with CFL lights... At least I'm learning a lot and, hopefully, my next grow will go smothly. Thanks again for everyone that is helping.
 

CrushnYuba

Well-known member
It's not that i think the dose of Epsom it's crazy. People use a tbsp (15ml) per gallon. It's just in relation to your other nutrients and the frequency that send way high.

1-2-2 is super low. 10ml per is the only phos source you got. I know you put the grow in their also but it doesn't add p. To give you an idea how low that is, i use a 16-16-16 for veg and a 10-21-21 for bloom. I would either give them 5ml per gallon in every single water or 15ml a gallon on every third water. I do that with a home made calmag using calcium nitrate and magnesium nitrate.

You don't have a calcium source either, which is the next most used nutrient other then n p and k. Your plants need like 2x as much calcium as mag.
 

Latino-grower

New member
It's not that i think the dose of Epsom it's crazy. People use a tbsp (15ml) per gallon. It's just in relation to your other nutrients and the frequency that send way high.

1-2-2 is super low. 10ml per is the only phos source you got. I know you put the grow in their also but it doesn't add p. To give you an idea how low that is, I use a 16-16-16 for veg and a 10-21-21 for bloom. I would either give them 5ml per gallon in every single water or 15ml a gallon on every third water. I do that with a home made calmag using calcium nitrate and magnesium nitrate.

You don't have a calcium source either, which is the next most used nutrient other then n p and k. Your plants need like 2x as much calcium as mag.

So, how much from my ferts do you think that would be an appropriate dose? I'm not supplementing the plants with calcium, but it doesn't seem like they are going through a calcium deficiency.

Here's some really good articles on growing in peat.

https://scienceinhydroponics.com/2017/04/using-peat-moss-in-hydroponic-culture.html


Google this: Harmonizing Peat and Lime - Sun Gro Horticulture
Then the link below should pop up. The link posted as is won't work properly when pasted on icmag.

https://www.sungro.com/issue-33-april-2005-harmonizing-peat-and-lime/

Cheers Absolem, very interesting stuff! Is difficult to find materials with this level of quality.

I didn't know that perlite and peat is considered as hydroponic, neither that peat is so complex. Actually, with those plants, I'm using a new supplier of peat for the first time, wondering if my problems are being caused by its quality...
 
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