LED feed demands

[f-e]

There is an oxygen requirement of water, that needs to be met at elevated levels, if we are too really use our lights.

Over watering causes a slump in performance. As I increase feeding duration and frequency, I am balancing this slump against the deficiencies onset by excess drying(while getting some runoff). The coco I use (canna) should be fine, even when soaked. Yet my little pots could become waterlogged enough for a struggling plant to be drown out. I started cutting it with perlite at the same time I started using h202, which helped with my personal situation. I reckon it was the h2o2 mainly. As I was running dirty. Hot and dirty. I had to back off and clean my act up. My tank was flat as last weeks beverage.


Exploziv, the more I look, I'm swayed from low Ca, towards over fed. Are their frames big and strong? in/out ec numbers?
I'm seeing some fully browned off leaves. Few deficiencies can do that. We can see it's not N deficiency. The most likely reason might be burning. Ca suppresses just about everything except N. So at a certain point, adding Ca could, perhaps, lead to a reduction in over feed signs. Just to chuck a spanner in the works.

I would feed one almost nothing, and double the feed to another. It's desperate but the knowledge gained could be very useful. Perhaps even the answer. A third could receive H2O2.

 

[GoatCheese]

Over watering causes a slump in performance.

When the over watering isn’t too bad but enough to show some leaf damage – little necrosis on few leaf tips and some brown spots and few leaves going little pale - i haven’t seen noticeable drop in performance. When it gets to the point where leaves start dropping off from slightest touch, then the growth stuns very clearly. So it all depends how badly and for how long the plants have been over watered.
When i started growing in soil 10+ years ago i used to ruin many grows with over watering, so i know the symptoms very, very well and the many levels of it.

 

[GoatCheese]

You guys have suggested the problem being with just about every chemical element and compound involved in cannabis growing - excess and deficiency. One day it’s this and next week it’s that. Few weeks after that it’s something else.
Sooner or later one you might actually try raising your lights extra 15-20cm when nothing else worked besides calmag abit.
I’ll leave you guys to it.

 

[exploziv]

Lights are up from 1 week ago and plants haven't been fed ferts for over one month. So far i haven't seen signs they getting better. But I'll leave them for a while to see. I will try to come up with the plant pics today, maybe it helps.

Edit: so far I can see the Mg stripes has started to appear clearly, they were there before but you had to go in and look for them to notice. Other than that.. they look... okish, but stunted (this might be from early flower transplant) and with lots of burned and curled leaf tips. Took the pics and will select and upload some today. Before adding the pics I must say they been neglected a lot, and had it way too hot over the summer as well, so yeah I don't ask too much from them but they should look a bit more healthy than this.
Now you guys can theoreticize over this or ask me anything. I know I am not the only one having these kind of problems all of a sudden, so hopefully this will help more people.

Pics:

 

[exploziv]

Well.. Ca excess would explain a lot of what I am facing. Could you guys tell me if 2 full tablespoons of epsom salts per 4L of soil is a good add in or too much?
Also, maybe the fancy marble soil covering has started breaking down and releasing Ca? Is that what marble does? Anyone know more about this?
I also seem to have a S defficiency there..
Is there anything organic to add for S?
Anyway, next grow I will take both the marbles and the epsom salt out of the ecuation so we'll see wjat happens anyway.

 

[exploziv]

Sorry, forgot S and iron:
And also, as this seems to be my mission now, to figure this out, I would love to hear about the simplest organic mix I could do so i don't have over or under ca?
I was thinking organic garden soil mix (unferted but contains some humus and compost) to which I would only add vermicompost maybe as 15% of the mix, then 10 % each of vermiculite/perlite for aeration and fluffyness, and maybe just a bit of spaghnum for acidity and if you guys would recommend some proper dosages for epaom salts or dolomite lime or calmag loaded zeolite or some other addons i could buy at home and garden stores or feed stores or garden stores it would be great. I do not visit growshops. I do not order online from them either.
I also happen to have a great collection of soil ammendaments so shoot some I might use in proper amounts for a good average mix and I might have them already. I just want a base that gives everything for a while, not even close to a hot mix. Thank you!

 

[f-e]

Whats the runoff numbers?
Roots good?
It sounds like the lighting is on low, just keeping them alive. You might be better to run it at normal levels, as that's the grow you want to make work. PCbuds has a full on approach, of learning how to keep up. He knows he is baking them, and is figuring how to feed them for those circumstances.

I can't help with a soil build. Things like pH amendment may or may not be needed. To be honest, I wouldn't try to make a soil until I knew the rest of my grow was in order. You could be fighting on too many fronts to really know what's shooting you down.

It's kinda expensive, but does anyone use that living soil product and LEDs? It's a compost really, with chosen microlife to keep it going for a full cycle.


I think they could of been fed quite high, and kept quite wet. We see some dark green and cupping that suggests a bit of both. Random areas rusting away without the symmetry of deficiencies. Dead bits going a bit gammy. I would be surprised to see impressive roots.

 

[exploziv]

You are right, I was keeping the light low hoping to manage to keep them happier.
The fact that I am using a led light bar design that barely fits the tent doesn't help. Since I won a regulae square led panel at a mars hydro giveaway recently i am gonna switch to that and use this one to veg my outdoor plants and vegetable seedlings. It certainly needs to be kept further away that I like to keep my lights, and light is very concentrated just under it so it doesn't help. The sp3000 is for sure a great commercial light, but doesn't fit my grow space, nor style.
also, i'm not really trying.to build soil, just add some nice organic nutes and fluffyness materials to some regular planter soil or soiless mix. If any guys want to tell me what other amendaments can I use to help with other aspects of the soil, that would be very helpful.
so far i did the planting mix for my seeds for next grow, it's soiless mix with perlite and vermiculite added.

 

[Greenheart]

Epsom salts for quick release S. Elemental Sulfur for slow release.

Amounts to use? That is anyone's guess I think. I definitely am using way more Epsom than the bag suggests.

 

[exploziv]

Thank you man! My epsom salts bag says nothing about dosage tho.. can you tell me what yours say? Or anyone else?

 

[Greenheart]

exploziv

Lawns 1/2 pound per thousand square feet
garden plants/shrubs 2 tablespoons at the base of each plant
plant food supplement
Toms/roses 1 teaspoon per foot of height every 2 weeks.
garden startup 1 cup per 100 square feet
houseplants 1 teaspoon per gallon of water every 1-4 weeks

Sooner or later one you might actually try raising your lights extra 15-20cm when nothing else worked besides calmag abit.
I’ll leave you guys to it.

I have a 32 W led 40 inches above my plants. Now that it is at the ceiling height my next option is to point it at the ceiling.

Moving the lights farther away helps. There should be some other solution. I have had way more "light" from other sources. My old bloom room was a 5'x9' vertical with an air intake just below the 860W cmh I was running with buds less than a foot from it. I really don't think that 32W of led is putting out that level of light.

There has to be more to this switch. So far increasing the secondary nutrients only got me so far. Next was ambient temperatures.

 

[f-e]

If you buy good commercial composts, anything you do to them is unlikely to make it better. I have first hand experience of a UK brands R&D site. The campus was large as a typical 'big school' where they had floors of full on labs for constant monitoring and adjusting of their output to meet the standards they require. You can't mix the same thing twice and get the same result, unless things like the weather also match. There is no fancy lab kit that they don't use.
What we can do, is leave it alone, to see if it is any good. If it's not, then switch brands or fix what's proven to be wrong. Which will probably be our handling of the product.
Hands up, I'm happy to admit it, I can't guess my way to a better mix, than the man in the white apron can make with his labs backup.
Right now I have been having problems, so must stick to the most basic proven method of one bag, one bottle. So that I know the problem can't be there. While you are mixing your own, you are on your own. I'm not even adding a few bacteria to my commercial product. A perfect grow is needed, before you can assess the differences these things can bring.
I'm on my knee's here. Please just buy something that works.

An ill plant put on a shady windowsill will usually get better. In low light, it will have enough of everything, and all the time in the world to get better. No pressure. It's the same for plants growing 24/7 they will do better after a rest. Four hours is usually nice if they are struggling. Lowering demand and giving them a rest is like convalescence for them. It's not fixing the problem though.

Sulphur.. that's an interesting one. Kinda hard stems that don't do much other then develop long red stripes. A sign more likely to be P or Mg. I have been up and down with sulphates and seen no change in my circumstances. They are useful for cleaning coco of the excess K and Na. I think it's S+ so will swap about with most cations, except Ca and Mg as they are ++. I'm reaching a bit though.. I could be off base.
Georges drew a lot of the deficiency/toxicity pics we are seeing. Here is the full set so you can look at S (and save a copy of the page) https://cdn.shopify.com/s/files/1/0...ciency-chart-jorge-cervantes.jpg?v=1572550439

Be careful using low light to fix things. Perhaps you will. It seems likely. However, ultimately you will turn the lights up again. The reigning internet champion is doing over a Kg a meter in about 10 weeks, using 450w. IIRC using all-mix and less feed than he expected. Gavita lighting, not just white+red.

 

[Greenheart]

Couldn't agree with you more. I've had a room going for 8 months. A healthy enough male and an unhappy female. I've tried the past couple months to get clones going with no success.

For years I had a bed about 13 inches deep full of life and fresh scrap with no problems getting things to roll. I've got some FFoF and some end of the year clearance premix I scored today. After 8 months of waiting for the female to come around it's time to get something up and going while I figure out the science project. There is always that shower stall I bloomed my first 7 grams in. She was such an adorable first plant! :yay:

 

[exploziv]

Thank you for coming in on that f-e. You are right. Will try to use the premium soiless planter mix I bought with just perlite and vermiculite (since they are chemically inert I guess I am free to add 5-10% of each for fluffiness. One thing that baffles me is that this premium compost has uncomosted pieces of wood, like there is no part of it where you can put your hand in and not get at least some small wood pieces. I used to think the quality of bagged soil with uncomposted matter is low. Can this be ok?
Contains vegetable compost, wood compost, coco fibers, lava rock pebbles and a cacl ph buffer. Ph 6.4.
Smells great so I will try to use it like that, just with perlite and vermiculite and see what I got.
I was planning to send old mix to soil analysis but after your advice I'll wait and see how the bought mix does first, and then decide what I send in later. Optimally I would want to send in the mix before and after a successful grow, so I know what I need to replace mostly. But first I need to get that decent grow. Honestly I feel like a noob now.
Regarding low light, I put them like that after I realised this grow is a fail. It had a bad start with 15-20 mbar VPD and hi temps. It made me decide to stop growing in summer.
The fact that they still look bad in low light is even more baffling to me.
Back to square 1, I guess! Thank you all for the help. If anyone has something to add, please do.

 

[Broggemann]

This thread is full of strange theories:
Why should a light source, which got none IR at all, dehydrate a leaf more than a light source with a massive amount of IR?
Thats completely the opposite of whats actually happening, plants under LED transpire a lot less than under the sun or comparable powered HIDs.
Less talk and theories, more data and facts.

Did you try running an EC between 3.0 and 4.0?
If not, you should try it...

Give them light, give them food, be happy.

 

[f-e]

Broggemann My HID grow used about 6L per meter, and my LED grows have approached 10L. Figures taken from the water meter that fills my tank, and measuring the runoff at each fertigation. This is a big difference. Made to look small when you see PCbuds water usage. Even with this consumption the Ca need was there, which is often thought of as a requirement due to less drinking. I don't actually know anyone else measuring water use accurately. Especially with history under both light types and equally productive healthy crops.
The reason plants loose water, isn't just the heat. Plants have pores called stomata, the size of which they regulate. There are numerous regulatory triggers. A few people have pointed to the position of their fans as influencing their problems. There is something to these transpiration stories that makes putting all that data together a worthy chore. Keeping an open mind to the fact IR wavelengths may have an effect on stomatal size.
Why do you say they transpire a lot less? I'm just filling my net, using about 4.5L per meter. This would be higher if they didn't get so dry between their two a day. Which will soon be moved to three.

 

[f-e]

Thank you for coming in on that f-e. You are right. Will try to use the premium soiless planter mix I bought with just perlite and vermiculite (since they are chemically inert I guess I am free to add 5-10% of each for fluffiness. One thing that baffles me is that this premium compost has uncomosted pieces of wood, like there is no part of it where you can put your hand in and not get at least some small wood pieces. I used to think the quality of bagged soil with uncomposted matter is low. Can this be ok?
Contains vegetable compost, wood compost, coco fibers, lava rock pebbles and a cacl ph buffer. Ph 6.4.
Smells great so I will try to use it like that, just with perlite and vermiculite and see what I got.
I was planning to send old mix to soil analysis but after your advice I'll wait and see how the bought mix does first, and then decide what I send in later. Optimally I would want to send in the mix before and after a successful grow, so I know what I need to replace mostly. But first I need to get that decent grow. Honestly I feel like a noob now.
Regarding low light, I put them like that after I realised this grow is a fail. It had a bad start with 15-20 mbar VPD and hi temps. It made me decide to stop growing in summer.
The fact that they still look bad in low light is even more baffling to me.
Back to square 1, I guess! Thank you all for the help. If anyone has something to add, please do.

As the bits compost, they will be a source of food, further down the line. Right now, they will play a part in aeration and resisting compaction.
Having bought a premium mix that's known to work, I wouldn't do anything to it. IMO vermiculite is really wet, for rooting, not finals. Perlite is watering down the compost, just making the pots bigger. Both are moving away from a known substrate and so could be the source of problems. As long as the soil is good, there is no logical reason to change it.


If I were to build my own soil. Mix my own feeds. Make my own lights. Run unknown temps and humidity. Unknown beans. Then get a problem. Where would I start looking.
The best game plan is to copy the most common proven techniques. Bagged compost. Bottled feeds. Known LEDs. Known plants. Check your water, and use RO if you must. Monitor RH and Temperature. Then it's possible to ask for help, and for many people to understand your grow.
Your pebbles are basically silicone. I doubt it's available in any great quantity. They will lead to extra surface compaction though. Then water distribution could be effected. So it's an unnecessary product, that could cause problems. We can complicate it further, with the acids and alkaline's poured over them, that another gardener might not, who in turn says they are fine. It's better to just stick to basics until you find the thing you are doing differently.


It great that some peoples grow just works. Usually they do. Nailing down problems can be a nightmare though. Constantly proving things are right, until the last stone is unturned. Where we find some plastic duck in the tank was offgassing.

I'm not sure I would be trying EC4 as my truncheons don't measure that high. IIRC the early one reached EC3 but was expanded for CO2 users. A typical under feed tends to yellow out a plant. Often N shows first as it's in high demand. All the big leaves will be lost. However I can't apply this knowledge to an unusual soil mix. Even the idea of feeding one high and one low doesn't hold, if the soil is actually out of wack. Weeks of water says it was quite strong.

 

[exploziv]

Cool, now that you calmed me down about the uncomposted wood bits in the premium soilless mix, I'll use that and see how it goes. I did add some vermiculite and perlite already to the starter pots but since they are 150 ml or smaller.. it won't matter once I transplant into bigger pots. Thank you for your time and knowledge shared here.

 

[f-e]

We all do what we can bud

Looking at S further, it's perhaps a constant for me. Most searches claim light veins are a root issue so it's just now that I realise this. It's the first sign I'm getting in this compost grow and it's been in recent coco runs early on. The other sign I have is some mild Mg stripes, on just one main lead that's particularly well lit. I have found my feed has the same NPK as canna's. Mine says 5ml while the canna chart says 5-7ml. I looked it up, as 5ml does seem low. Perhaps my move to 6ml is the 20% more feed that will address this need for epsom salts.


Strong signs of yellow veins, accompanied by N deficiency showing in the red petiole extending into the leaf. I have the red stripes to some branching, but one difference. This starts at the very bottom. In the tiny leaves. This one in the pic is a bit random, as it's in a larger leaf and more advanced. Still at the very bottom. Perhaps I had a deficiency long ago, that's just showing.

 

[exploziv]

Thank you all for coming in on this! As I really want to get the problem fixed I invite each any any of you that wants to come and follow my next grow and maybe help me along the way to have a seat in my new thread:
https://www.icmag.com/forum/icmag-v...gends-cookies-mandarine-auto-under-m-h-fc3000