This is my first real grow!

[Eledin]

Whats the humdidity and temperature?

 

[mstrpkl]

Whats the humdidity and temperature?

Temps fluctuate between 60 and 70 degrees, humidity goes between 55% and 65%. Trying to keep the VPD between 0.8 and 1.1, those are the temps and humidity that will make that happen at the elevation im at

 

[mstrpkl]

Dont worry she will go back to normal. If it was a few days since the last watering there's no way your gonna cause permanent damage by overwatering a bit.

I think shes gonna be fine too, im pretty good about making sure the soil dries up a bit before watering again.

Weird thing this time though, those leaves were drooping yesterday so i poked the soil with my finger and it still felt pretty moist, only reason i didnt water yesterday. But then today the leaves were way more droopy so i figured maybe the water deeper down is all used up and the water closer to the top didnt get used for some reason? Would be really weird if that were the case lol but yea il post another picture later tonight, probably an hour or 2 after lights on

 

[PooToe]

Dont worry she will go back to normal. If it was a few days since the last watering there's no way your gonna cause permanent damage by overwatering a bit.

Agree. She's mature enough that a little overwater shouldn't do much other than a temporary slowdown.

 

[Eledin]

I think shes gonna be fine too, im pretty good about making sure the soil dries up a bit before watering again.

Weird thing this time though, those leaves were drooping yesterday so i poked the soil with my finger and it still felt pretty moist, only reason i didnt water yesterday. But then today the leaves were way more droopy so i figured maybe the water deeper down is all used up and the water closer to the top didnt get used for some reason? Would be really weird if that were the case lol but yea il post another picture later tonight, probably an hour or 2 after lights on

Temps fluctuate between 60 and 70 degrees, humidity goes between 55% and 65%. Trying to keep the VPD between 0.8 and 1.1, those are the temps and humidity that will make that happen at the elevation im at

If that 65% humidity mixes with those 60 degrees I can see the soil being wet for more than a couple of days and not needing to water, and even the plant getting droopy, the VPD with that mix is also 0,45 kPa which is not in the danger zone but close.

 

[Eledin]

Low VPD: The air is cold and humid, which slows water loss from plants. This can prevent them from absorbing enough nutrients, causing deficiencies and slower growth.

An Easy Guide to VPD

How to Use VPD to Increase Your Yields Many growers believe that the most important things in growing are the light and the nutrients. Light and nutrients are very important, but plants can't use either of them properly unless the environment lets them. About Transpiration Plants need to lose...

www.onestopgrowshop.co.uk

And needless to say they will also drink slower since they cant evaporate moisture and the soil wet for too long caused the droopyness.

 

[mstrpkl]

If that 65% humidity mixes with those 60 degrees I can see the soil being wet for more than a couple of days and not needing to water, and even the plant getting droopy, the VPD with that mix is also 0,45 VPD which is not in the danger zone but close.

Yea luckily the only time it hits 65% is during the day as far as i know. I can definitely say the very lowest i see the VPD touch, and only for a second, is 0.6, which is still a little low but nothing to freak out about at this stage in the grow

 

[mstrpkl]

I might have to turn the temps on the space heater in the lung room up a bit to help manage the soil a little better. I think itl be better if i can keep it closer to 65-75 degrees

 

[mstrpkl]

Here she is after the light turned on, so about 8 hours after i gave water. She looks much happier :)

 

[PooToe]

I might have to turn the temps on the space heater in the lung room up a bit to help manage the soil a little better. I think itl be better if i can keep it closer to 65-75 degrees

My recommendation is run your lights on air temps in the tent at 80° and your lights off temps at no lower than 70°. Keep your humidity at around 55% during veg and 45% during flower. If you want to get even more precise you can buy a laser thermometer, they're around $20 at Walmart, and measure the leaf temp. 77° is what you're looking for.

Those specs should keep you in the green zone or close to it throughout the grow. Keep in mind that VPD specs fluctuate with the difference between leaf and air temp. A difference of 0° at 80°/55% shows a VPD of around 1.52. A 5° difference means the VPD at 80°/55% is now around 1.09. Big difference.

The VPD readings you get from your controller are estimations at best. Your probe can't measure leaf temp only air temp. The app is using a default air/leaf difference. Probably 3° which is sort of middle of the road so the reading you are getting is not the exact reading.

Dimlux has a good calculator with charts from 0° swing to 5° swing if you want to know what the exact VPD number is when you measured it.

Vapor Pressure Deficit VPD Calculator - Dimlux Lighting - The Best Grow Lights

Vapor Pressure DeficitCalculator Calculate both Room VPD and Leaf VPD automatically Just enter the value below to generate the VPD values for your room and your plants. You’ll need to know the room’s temperature, relative humidity, and the plant’s temperature. We recommend calibrating your...

www.dimluxlighting.com

 

[mstrpkl]

My recommendation is run your lights on air temps in the tent at 80° and your lights off temps at no lower than 70°. Keep your humidity at around 55% during veg and 45% during flower. If you want to get even more precise you can buy a laser thermometer and measure the leaf temp. 77° is what you're looking for.

Those specs should keep you in the green zone or close to it throughout the grow. Keep in mind that VPD specs fluctuate with the difference between leaf and air temp. A difference of 0° at 80°/55% shows a VPD of around 1.52. A 5° difference means the VPD at 80°/55% is now around 1.09. Big difference.

Dimlux has a good calculator with charts from 0° swing to 5° swing.

Vapor Pressure Deficit VPD Calculator - Dimlux Lighting - The Best Grow Lights

Vapor Pressure DeficitCalculator Calculate both Room VPD and Leaf VPD automatically Just enter the value below to generate the VPD values for your room and your plants. You’ll need to know the room’s temperature, relative humidity, and the plant’s temperature. We recommend calibrating your...

www.dimluxlighting.com

I really wish i could manage the temps better, but being in the mountains it gets really cold in the winter, and i cant really keep my heater on above 63 because propane is expensive as fuck lol i turned my space heater up by 5° so wel see how that does, hopefully it makes a good difference.

As always, i appreciate the info man!

 

[PooToe]

If you can position your space heater near the intake on your tent you can control your temperature better and be able to raise the temp in the tent.

When you run the tent at that temperature/humidity you're going to see some explosive growth unless the genetics says otherwise but, judging from your recent pics, that doesn't seem to be an issue!

 

[mstrpkl]

If you can position your space heater near the intake on your tent you can control your temperature better and be able to raise the temp in the tent.

When you run the tent at that temperature/humidity you're going to see some explosive growth unless the genetics says otherwise but, judging from your recent pics, that doesn't seem to be an issue!

Its so much easier to manage temps in the summer plus the space heater i have in there isnt the best. Its reliable at least, but it doesnt manage the temps very well lol annoying but i dont have any money to drop on a new one righmeow :(

 

[Eledin]

Can you decrease airflow to increase temp? Maybe even reverse the fans from top to bottom instead

 

[mstrpkl]

I think my best bet is to change my exhaust setting. I have it set to run conatantly at the lowest speed, sort of like a "standby" setting. I wanted to make sure the plant has lots of air flow coming into the tent, but maybe i need to set it to just run for a minute or 2 every couple hours or something. Thatl let the heat from the lights fill the tent, instead of being sucked out immediately and the tent matching the room temps. Plus itl save me some distilled water in my humidifier lol

 

[Eledin]

I have different size fans depending on the time of the year. Theyre cheap ass in line fans with no power regulation thats why I have a few hahaha. For winter I use the 100mm ones, for summer I use the 150mm ones in the big tent and the 125mm one in the small tent cause the big one doesnt fit.

 

[PooToe]

If you locate the heater near the bottom intake port it will draw warm air into the tent as the exhaust fan pulls in the air. Along with the light heat it should raise the temp in the tent. You can find the perfect spot by experimenting a little with fan speed. Maybe turn on and off your minimum speed every hour?

IIRC, you aren't venting the exhaust out of the lung room so the heat that the lights generate, along with the heater, should raise the temp in the lung room and in the tent.

 

[mstrpkl]

I have different size fans depending on the time of the year. Theyre cheap ass in line fans with no power regulation thats why I have a few hahaha. For winter I use the 100mm ones, for summer I use the 150mm ones in the big tent and the 125mm one in the small tent cause the big one doesnt fit.

If you locate the heater near the bottom intake port it will draw warm air into the tent as the exhaust fan pulls in the air. Along with the light heat it should raise the temp in the tent. You can find the perfect spot by experimenting a little with fan speed. Maybe turn on and off your minimum speed every hour?

IIRC, you aren't venting the exhaust out of the lung room so the heat that the lights generate, along with the heater, should raise the temp in the lung room and in the tent.

I think i got it set to a good spot now :)

I set my exhaust fan to only turn on the lowest speed when the tent hits 79°, just to make sure it doesnt go past 80°. The new high in the tent is 79.6° and im assuming the new low will be in the mid-low 70s. Hasnt run with lights off yet.

But weirdly enough, turning the exhaust fan off until the temps rise in the tent has made a big difference in the temps of the lung room. Wouldnt think it would affect it that much, but literally raised temps in the lung room by 5°-10° on average. Crazy, didnt realize i had the airflow optimized for cooling lol

Im planning on trimming her in the next day or 2, whenever the watering is scheduled. Most likely gonna top on the same day, assuming shes ready for it. She looks pretty ready hut i havent counted the nodes in a while so im not 100% sure right now

 

[PooToe]

Nice.

Watch your leaves to see how the plant reacts to the rise in temp. Once you see how she reacts, if it's positively, then you can start messing with light energy and see how the puzzle completes itself. The rise in temp will spur more photosynthesis which will require more light energy to try and max plant performance. Your light levels may be fine as they are but, as I said, you can play with it a little to try and find its sweet spot.

 

[mstrpkl]

Il definitely be messin with it over time haha

Noticed something today though. Looks like some leaf tips on some new growth, specifically at the top, has yellow/burnt tips. Maybe iv had the light inensity set too high with the lower temps?