I’ve a mind-trick for that : your water/nutes for cannabis should be an oxygenated river, it’s why the NFT method is so impressive with this plant in general. If your moisture stay too long, it become a pond.
The advantage of the coco over the soil is its quality of “sponge” in regard of its kind of retention. Much more homogeneous that soil that have tendances to create “strata” of different moisture. In this last case, you can have dry parcel just aside parcels that never entirely dry and become stagnant (in the sense of a pond). The lack of oxygen and the accumulation of nutes by lack of gas exchange, make wounds on a branch of the root mass and when it happend … you get necrosis. The “wet ones”, dark and soft to the touch. The “dry ones” are bright light brown and crunchy (another type of problem).
The very yellow chlorosis (like canary) happening after is just a secondary symptom of wounded roots not doing their job of assimilation.
The fastest way to fix it is to cut the carbon rate of your medium (on nutes side), water it enough to get ~30% drain of what you’re pouring then using gravity to “drain manually” the medium. It can be summed up by moving the pot up and down until there is not a single drop falling from the bottom of the pot (can be long). One time it’s manually “semi-dry”, pour half dose of your nutrients + fulvic acid full dose (for a 1:400 concentration) and wait the magic 48 hours.
That’s so valid point and I specifically agree with the last part to dim down the light a lot at this point.
Think water imbalance is caused by both strong light intensity and high transpiration.
Rhubarb effect is pretty severe. Humidity deficit and extreme air movements are changed. I can only think of light intensity at this point.
Worst case again some fusarium sort of but i doubt it.
p.s. But little confused
Cuz pics two days ago don’t have that much starch accumulation on petioles
That’s why i thought light intensity ain’t problem but picture yesterday has a looooooot of starch in the plants.
You lit the way actually ^^ My familiarity with coco just helped to cross off a bunch of options. And they are looking too nice and full of potential to don’t fight against a strong, and constant, limiting factor.
The duration of the post make me think also about the experiments i’m actually doing on static pressure / ACPM (air change per minute) with the exact same tent dimension and the same CFM flow. That, with an unusual light setup (on the high range of refraction).
Symptoms are less visible, but i’m sure you will see the funk with the restricted phototropism : only on shoots. I got a decent sap pressure only with very particular nutrients (controlled) abuses that are boosting as fck the gas exchange/CEC on roots. It last one day top.
The plants now that my body is a wreck to totally rebuild the prototype since a half week :
36W of T8, no air exchange at all, 80% RH, phototropism at max and sape pressure like a Kärcher washer ^^
I’m firmly think that in reducing drastically the both parameter suddenly on the plants under chock will permit to know within 48 hours if one or both of these parameters are the black hole to hunt, or not.
Struggle to understand what some of you are saying. I figured out my ac69 controller and can now officially dial in a temp and humidity so I’ve ran 73/76 the last 24 hours. When I water I’m barely watering any. So in 36 hours the plants maybe got 1cup or so water.
Saw a little fly today, killed it and sprayed plants a bit. Put some sticky traps too as you all suggested. The plants are looking better for most part.
Issue I have I think is they’re so short and stocky. It’s hard to water as all the leaves are so close to soil I have to lift all them to pour water in. I can’t get them to grow at all. My tallest is barely over a foot with tons of shoots on it…. Would have exptexted 2 foot plant for amount of nodes/shoots. I turned light up hoping they’ll stretch
That’s the opposite of what you would want to do. If you want to promote vertical growth, dim your lights. It makes the plants “reach” for the lights. Not suggesting that is the proper course of action here, just a general principle.
They look fine with the changes you’ve made. Patience grasshopper .
In very synthetic/short/raw : a lot less light (dimmed 50% and pushed in roof of tent) + less negative pressure during 48 hours (unzipped), and they are supposed “to prey”. The leaves in “V shape”. Because the symptoms.
Or just LIFTA and wait that they grow enough (1’) to let them overcome the limiting factor (whatever it is).
@TomHill suggested that I go 15/9 on lights and it made my stubborn deep chunk take off! I wasn’t sure if it would work but it is great technique and works for other types that I grow.
Oh that’s impressive actually
Wonder the detail of your experiment!!
I haven’t really considered sap flow
I mean i do not know how to sense it besides using the sap flow measuring device. Would be so glad if you share simple way of sensing the sap flow🙏
And holy moly set up’s nice but specifically that 36W set up is mad
It is just perfect space efficiency and plants growth look uniform with good internodal spacing🔥
Great to hear that there is some improvement
Though, few things you can do for longer internode is
Increase temp
Increase water availability (both relative humidity and water contents in your soil mix)
Lower the light intensity
Number 1 and 2 can be achieved by not running the vent at all, if humidity is below 80% at 25’C (or match to humidity deficit around 5; see the chart i sent above or you can ask me)
Number 3 can be achieved by keeping further distance between the lights and plants or dimming down the light power as you know
If done correxty older internode won’t stretch but newer ones will have longer internode!
You are doing awesomely good
It won’t take long to fix it
I’ll turn down light intensity and leave them high then. I’m also running 75*f and 78RH.
I safe to go to 75*F and 80-82 RH or so the RH then to high ?
Someone suggested going to 18/6 from 24/0? If I do that I have to deal w warming tent during lights off and prefer not to do that but does that help intermodal spacing a lot?
Oh with 75’F (24’C) you can aim 75% RH. Once they are very very stable we can lower RH a bit more around 72% but for now 75% for extra buffer! 80% can be little too high atm.
Also if you have been running with 24/0, you can change to 18/6.
That will help longer internode spacing for sure!(photosynthesis is producing of sugar and respiration is use of sugar. Sugar is energy for plants to work. When 24/0 cycle, photosynthesis may be too high compare to respiration as lights on whole time, that it may hinder internode to stretch)
Also, it is nice idea to increase temp during plant night time but it is not always necessary. That will increase yield or so but considering energy cost, it has high chance not worth increasing temperature at night time. As long as temp at night is over 15’C, it will do the job.
If some words are not familiar to you, let me know
I can explain.
Many words in horticulture scene isn’t common to us and also terminology can differ by countries so it def is natural to feel bit off with some parts!
Short and stocky is good. You don’t want them growing tall now they will do that when you flip.
I think you’re “helicopter parenting” these plants. Doing too much. Slow down, water less, stop trying to correct every tiny thing you see because you’re going to end up doing 100 different things and even if one of them is right you’ll never know what it was.
Don’t tell anyone ^^ And yes, i’m a pretty empiric guy. I got the idea in talking about homemade maple syrup with a Canadian friend. It’s when phenotype observation is not enough and that i’ve to corelate volume of sap/hour with specific root activity.
The 36W setup is my grow desk actually, where i manipulate/analyze the plants and look at them in details. Above it’s the fan for my blunts ^^, exhaust duct unmounted. They are here because i’m actually rebuilding the tent to extend the experiment on Static Pressure. It make me mad to seeing them enjoying so much this transitional space.
Moved power down a bit and moved lights back to 18/6 once again to help spacing. Going to ride it out from here and not make anymore changes. I think things are recovering very well. Even the badly burnt plant seems to be coming back
I have a bunch of stocky wide thick plants that just kept going out rather than up.Stalks at round as Cafeteria Pretzels.I had them on wooden Tv dinner tray stands about 30 inches from the light the whole time they been growing.I dropped them to the floor and turned the light down it’s a smaller Sonlipo light bright little bastard.lights at about 75 inches up now and all them plants the day I did that started stretching just did this yesterday.Came home them little shits grew at least an inch and the node space is growing too.My afghan heirloom was not greening up right stayed a yellowish pale green put it on the floor days ago and the color improved and it’s starting to go full green now.Sometimes the distance of that light makes all the difference
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