Snerval's third grow - BioTabs

[Bob's Auto's]

Plants don't drink much right now, I give them around 800 ml plain water every other day or so.

That's still quite enough water for one plant. If you optimize your VPD, then the plants get more room to breath out moisture and so speed up the process of taking up water and nutrients. These make the plants grow faster and faster. And as long if you keep that VPD in check at all times it will keep accelerating. At least that my experience at the moment, the fact that I can see how the plants responded via that time lapse compared to the data from my app is great learning material. I would love to incorporate that information into the time lapse so it becomes clear to everyone. Just don't have the skills to do that with the VSDC program I'm using to make the time lapse with.
Sorry I'm babbling...

 

[snerval]

Sorry I'm babbling...

Don't be sorry I love to read educated babbling !
I'm concerned about the RSB though - one big central trunk, almost no branches and buds appearing almost ON the trunk lol !
Oh well, my goal isn't to harvest a maximum of flowers - I can't smoke or vape anymore, so I need small amounts to make my tinctures... and soon hopefully some cobs to chew ! I just hope I don't screw up the THC level this time...

About VPD - I've read that there's a difference between Room VPD and leaf VPD.
And I who thought I knew enough to master this notion...
My sensor is placed at the top level of the canopy - do you think the data I'm getting is enough to handle the general VPD ?
Or is it absolutely necessary to master leaf VPD ?

 

[Bob's Auto's]

I've placed my sensors level with the lower pheno's from the S.o.S. and placed the larger plants on the outside where the light output is lowest. I feel that the sensor give the most accurate values for the plants. In my calculation I take into account that leave temperature is always 1.3°C lower then the environment. This gives me good results. If you want you can get small thermistors which you can stick on a leaf and measure it's temperature, but that's cumbersome and you'll probably get the same results.

 

[snerval]

I've placed my sensors level with the lower pheno's from the S.o.S. and placed the larger plants on the outside where the light output is lowest. I feel that the sensor give the most accurate values for the plants. In my calculation I take into account that leave temperature is always 1.3°C lower then the environment. This gives me good results. If you want you can get small thermistors which you can stick on a leaf and measure it's temperature, but that's cumbersome and you'll probably get the same results.

I happen to have an infrared, no contact thermometer similar to this one : https://tinyurl.com/4cu4f22u
I used it to cook my coco infusions when I was living in India - since my moving to France I purchased an Ardent FX which facilitate decarb & cooking greatly...
Maybe I could use it to get the leaf temp ?

 

[snerval]

I just hope I don't screw up the THC level this time...

I would like to point out that my cannabis ended up low in THC due to the 6 successive waves of heat wave that we experienced during my second crop, last summer...
Unfortunately I couldn't manage heat during the grow AND the drying period

 

[Bob's Auto's]

I happen to have an infrared, no contact thermometer similar to this one : https://tinyurl.com/4cu4f22u
I used it to cook my coco infusions when I was living in India - since my moving to France I purchased an Ardent FX which facilitate decarb & cooking greatly...
Maybe I could use it to get the leaf temp ?

Yeah, you can try to use that, although I don't know if these cheaper laserthermometers are any good on green surfaces, with all the red spectrum being absorbed by the leaf...If you need to remove a leaf you can test this out. Take that leaf and ligh it flat on a piece of paper on the table. Wait a couple of hours and measure both paper and leaf. Both should have the same temperature. If it's not one can asume the chlorophyl is absorbing some of the light.
I know they use very tiny thermistors at the WUR. The stick them on the underside of the leaf, they do that for about ten leaves. The take an avarage of those datasets and that's the leaf temperature. In greenhouses under sunlight the leaf temperature will be closer to 0.8°C / 33.44°F lower from the environment, but indoors under led light, the temperature is more likely 1.3°C lower. This has got to do with the light spectrum...But again, I'm babbling...Sorry I'm stoned This reminds me...Be back in a minute or two...

 

[NORB YIPPLS]

Don't be sorry I love to read educated babbling !
I'm concerned about the RSB though - one big central trunk, almost no branches and buds appearing almost ON the trunk lol !
Oh well, my goal isn't to harvest a maximum of flowers - I can't smoke or vape anymore, so I need small amounts to make my tinctures... and soon hopefully some cobs to chew ! I just hope I don't screw up the THC level this time...

About VPD - I've read that there's a difference between Room VPD and leaf VPD.
And I who thought I knew enough to master this notion...
My sensor is placed at the top level of the canopy - do you think the data I'm getting is enough to handle the general VPD ?
Or is it absolutely necessary to master leaf VPD ?

They all look great.
I've had plants grow the same as your Banana girl.
I found that removing the upper fan leaves and raise it up closer to light gets the branches to stretch better.
I think its possibly not enough light that causes it. Or ppfd is lower around that certain plant.

Moving it closer to the light should get them to stretch
Keeper lit, looks great in there

 

[snerval]

They all look great.
I've had plants grow the same as your Banana girl.
I found that removing the upper fan leaves and raise it up closer to light gets the branches to stretch better.
I think its possibly not enough light that causes it. Or ppfd is lower around that certain plant.

Moving it closer to the light should get them to stretch
Keeper lit, looks great in there

Thank you for stopping by ^^
During my last (second) grow I had an RSB with weird genetics - the leaves were twisted. I binned her on @Bob's Auto's advice because she would have only brought trouble... this one RSB is from the same batch from Seedsman...
Maybe I came across a compromised seed batch ?
Anyway, thanks for your advice, I'll give it a try.

 

[snerval]

So here's the RSB girl today after removing the upper fan leaves and moving her closer to the light :

@NORB YIPPLS should I remove the 2 medium fan leaves at the very top too ?
She's definitely a strange looking plant haha !

Here's my little garden, all is looking ok as far as I can tell.
Yesterday I feed them with 3ml/l of BioTabs PK 5-8, to encourage the grow of buds sites - @Bob's Auto's they reacted very well, no problem that I can see

Thanks for watching et bon week-end à tous !

 

[Bob's Auto's]

Yesterday I feed them with 3ml/l of BioTabs PK 5-8, to encourage the grow of buds sites

If you are going with 3ml/L from the beginning, then I recommend you do at least two waterings without the product. Give the plants time to react to the change in the soil.