Stunt Growth in seedlings . In search of a solution

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goodbye95

goodbye95

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Hello Everyone ,
I have a problem with my current grow and i would appreciate your opinions on how to solve it.

The strain is " Green Gelato " by Royal Queen Seeds
I currently run a complete automated system via a controller
Fans, Lights, Humidifier, Dehumidifier are all tuned by the controller
My current grow tent is 3/3 feet
The lights i use are the Spiderfarmer SF7000 ( 650 w)
Current medium : Coco coir 65% - Mycorrhiza 5% (it was mixed in the coco brick) - 30% Perlite
The plants are in 250ml pots with 10 holes in each side and 8 holes at the bottom for better drainage and oxygen exchange.
Below the Coco there is about 2 cm of Clay pebbles.
There are also 3 circulating fans inside the tent.

So my grow diary goes like this :

Day 1:

I put the seeds in wet paper towel to germinate with tap water

Day 3:

The seeds have germinated with the tail being about 2cm long 10/10 SUCCESS!I
I place the seeds about 0,5 cm from the surface and cover with coco.

First watering :
20 ml water in each plant in a circle around it ( No Nutes , except for Root Stimulator )
Ph : 6
PPM : 150
Lights at 10 % intensity at 132 cm
Day Temp : 26 C
Day RH : 73 %
Night Temp : 25 C
Night RH : 70 %


Day 7 :

Second watering :
20 ml in each plant in a circle around it ( No Nutes , except for Root Stimulator )
Ph : 5.9
PPM : 145
Day Temp : 26 C
Day RH : 73 %
Night Temp : 25 C
Night RH : 70 %
Leaf Temperature ~ 25,5 C both day and night


Day 8


Temps are the same but leaf temperature rises at 26 C
So i bring up the RH at 75 %


Day 11

Third watering :
60 ml in each plant ( No Nutes ,except for Root Stimulator )
Ph 5.9
PPM : 234 ( Ph up solution has raised up my PPM , i do not know whats in it )
Day Temp : 27 C
Day RH : 72 %
Night Temp : 26 C
Night RH : 68 %
Leaf Temperature ~ 25.2 C


Day 12

The plants have become a little yellow and have stopped completely growing so i lower a little my LVPD to
lessen the obvious stress . I thought i have overwatered cause of the 40ml add in the last watering so i raised the RH )

Day Temp : 25.5 C
Day RH : 80 %
Night Temp : 25 C
Night RH : 75 %
Leaf Temperature : 26 C


Day 13

The colour of the leafs has become a little more green but the growth is still stunned
Day Temp : 25,5
Day RH : 82 %
Night Temp : 25.5 C
Night RH : 78 %

Day 14

The same values as day 13.
Still plants are stunned. The Leaf Temp for some reason has raised to 26.5 C !!



Mostly i base my Temps and RH to provide the leafs a VPD of 0,6 - 0,8

I have not add any Cal-Mag in my waterings or any other grow / gloom nutes for the time being if that
plays a part.


The photos I provide below are today , on Day 15 .

Do not be fooled by the colours that my phone camera captures. This is not the green our eyes see . The plants are a little more yellowish.
 
Stunt growth in seedlings  in search of a solution
Stunt growth in seedlings  in search of a solution 2
Stunt growth in seedlings  in search of a solution 3
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Shaded_One

Shaded_One

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I'm not a coco guy myself but from what I understand you need to be watering coco daily and not letting it dry back otherwise you run into massive issues.

Aside from that you might wanna look into some earth worm castings or compost to induce some microbial life.
 
Homesteader

Homesteader

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Sometimes the growth is slow those first few weeks but it definitely could use some Nitrogen which will help a lot. If it were my plants, I would be giving each of them a shot of fish hydrolysate
 
goodbye95

goodbye95

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To add to my first post . If you can see in the pictures the end of the leafs is quite dark green and the rest of the leaf towards the stem is yellowish. I also do not prefer to water everyday to this phase because there are no roots developed yet. From the last watering 5 days ago the water has not moved more than 1.5 cm from the surface of the medium so its a fact that there is plenty of water inside and i do not want ro risk overwatering once more. I plan to give some nitrogen in the next watering targeting around 400 PPM. Of course that depends on what i will learn from this thread.
 
Shaded_One

Shaded_One

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263
To add to my first post . If you can see in the pictures the end of the leafs is quite dark green and the rest of the leaf towards the stem is yellowish. I also do not prefer to water everyday to this phase because there are no roots developed yet. From the last watering 5 days ago the water has not moved more than 1.5 cm from the surface of the medium so its a fact that there is plenty of water inside and i do not want ro risk overwatering once more. I plan to give some nitrogen in the next watering targeting around 400 PPM. Of course that depends on what i will learn from this thread.

No offense but coco doesn't care what you want - it needs to be watered daily and as the plants grow that will increase to multiple times a day.

I think you need to do some research on growing mediums and understand what you are using and why.

I have 4 day old seedlings in soil that get watered daily. You are in coco.
 
goodbye95

goodbye95

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No offense but coco doesn't care what you want - it needs to be watered daily and as the plants grow that will increase to multiple times a day.

I think you need to do some research on growing mediums and understand what you are using and why.

I have 4 day old seedlings in soil that get watered daily. You are in coco.
I followed your advice and watered again about 50 ml for each plant at about 275 PPM. PH 5.9 . I will provide the news in some time. 10 mins after the watering and the leaf temperature already dropped to 25 C.
 
Shaded_One

Shaded_One

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I followed your advice and watered again about 50 ml for each plant at about 275 PPM. PH 5.9 . I will provide the news in some time.

Don't be scared of water. Coco with perlite is such a high porosity medium that water funnels through and doesn't get soggy at all. So unless you're letting the pots sit in constant run off and you're not letting them dry back then you shouldn't have over water issues ever. That's the main reason people use cico/perlite is for the extremely high porosity and drainage. But this means you need to water more frequently.

Hopefully that helps a bit!
 
goodbye95

goodbye95

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Don't be scared of water. Coco with perlite is such a high porosity medium that water funnels through and doesn't get soggy at all. So unless you're letting the pots sit in constant run off and you're not letting them dry back then you shouldn't have over water issues ever. That's the main reason people use cico/perlite is for the extremely high porosity and drainage. But this means you need to water more frequently.

Hopefully that helps a bit!
Thank you man. Really appreciate. I knew that i need to water coco every day but last time i overwatered my plants in the same pots so now i am a little more fearful. Since the yellowing i commented above came after the sudden spike in watering volume i thought i did it again. I have been overwatering the last 4 grows. I ve killed like 40 seeds till now in a matter of 5 months and paid like 100 euros for every 10 of them. So i think you understand my hesitating actions
 
Shaded_One

Shaded_One

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Thank you man. Really appreciate. I knew that i need to water coco every day but last time i overwatered my plants in the same pots so now i am a little more fearful. Since the yellowing i commented above came after the sudden spike in watering volume i thought i did it again. I have been overwatering the last 4 grows. I ve killed like 40 seeds till now in a matter of 5 months and paid like 100 euros for every 10 of them. So i think you understand my hesitating actions

I can definitely understand you're hesitation. I don't grow in coco but I do use very high porosity soil that I tend to treat like coco aka I water quite frequently. The pots get fully saturated until a tiny bit of run off and then I let them dry back.

My soil has EWC added so they get enough starter nutrition for a few weeks and this is where my education for you is limited. Might need @Aqua Man to help you out with starter ppm etc for the first couple of weeks as I really have no clue.
 
goodbye95

goodbye95

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ps try to get your RH to the 60-65% range 70-80% is really messing up the transpiration
I know but the climate does not let me . I do not have an air condition so i move my tent temperature as low as the room ambient temperature lets me. So in order to have the leaf vpd under 0.8 that is the lowest i can go in temps and Rh.
 
PipeCarver

PipeCarver

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I know but the climate does not let me . I do not have an air condition so i move my tent temperature as low as the room ambient temperature lets me. So in order to have the leaf vpd under 0.8 that is the lowest i can go in temps and Rh.
If you intend on growing you're going to have to control the environment somewhat. Humidify if too dry and dehumidify if too humid. Fans to keep the air moving will help with the temperature as they can take the heat but without the humidity. Buds don't do well in high humidity and mold can set in pretty fast
 
Aqua Man

Aqua Man

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I can definitely understand you're hesitation. I don't grow in coco but I do use very high porosity soil that I tend to treat like coco aka I water quite frequently. The pots get fully saturated until a tiny bit of run off and then I let them dry back.

My soil has EWC added so they get enough starter nutrition for a few weeks and this is where my education for you is limited. Might need @Aqua Man to help you out with starter ppm etc for the first couple of weeks as I really have no clue.
Depends on the nutrients used but typically you start at about 400ppm and work up to 800ppm
 
goodbye95

goodbye95

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Depends on the nutrients used but typically you start at about 400ppm and work up to 800ppm
ps try to get your RH to the 60-65% range 70-80% is really messing up the transpiration
You both saved my time once more and once more i have improved my knoledge by a little more. It seemed that all these days the plants were having lack of water and nutrients. I watered my plants yesterday about 100 ml and i watered again today till runoff (about 140 ml water and about 50 ml runoff ) and as @Shaded_One said , indeed i had to water every day in coco and indeed there was space to do it. The plants had their colour returned and signs of growth have already started.

I have one more question for you which i do not want to ask in another thread since i believe its easy to answer
I always water at 5.9 PH and today i watered at about 450 ppm. My runoff though was at 6.7 PH and my ppm at about 650.
How to adjust my PH and PPM every time to keep the PH and EC at a stable frame. For example in the next watering how much should my PH and PPM be in order for the runoff water to be at 5.9 PH and the ppm at less than i have fed the last time? ( which means that plants have consumed some of the nutrients i have provided i suppose )
 
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Aqua Man

Aqua Man

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You both saved my time once more and once more i have improved my knoledge by a little more. It seemed that all these days the plants were having lack of water and nutrients. I watered my plants yesterday about 100 ml and i watered again today till runoff (about 140 ml water and about 50 ml runoff ) and as @Shaded_One said , indeed i had to water every day in coco and indeed there was space to do it. The plants had their colour returned and signs of growth have already started.

I have one more question for you which i do not want to ask in another thread since i believe its easy to answer
I always water at 5.9 PH and today i watered at about 450 ppm. My runoff though was at 6.7 PH and my ppm at about 650.
How to adjust my PH and PPM every time to keep the PH and EC at a stable frame. For example in the next watering how much should my PH and PPM be in order for the runoff water to be at 5.9 PH and the ppm at less than i have fed the last time? ( which means that plants have consumed some of the nutrients i have provided i suppose )
This is how you keep a good control of the rootzone.

are you using tap or distilled and what nutrients?

 
goodbye95

goodbye95

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This is how you keep a good control of the rootzone.

are you using tap or distilled and what nutrients?

I use tap water which i have inside a bucket with a bubbler working 24/7 . I use Biobizz nutrients.
 
Aqua Man

Aqua Man

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I mean its not a bad thing to do but a couple hrs will stabilize the gasses and PH.

if you want to rid it of chlorine or chloramine you can use 1 gram per 100gal of ascorbic acid (vitamin C)
 
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