Amen, brother. I’m a T4 paraplegic of 18 years die to a gunshot, so I LOL’ed at ’walking out’. Life’s good!
Pruning questions
- Thread starter wheelyman
- Start date
Oh yeah then I’m running hot. Esp with tap water. Will back off. And I believe it’s around 60% RH and 74 degrees? Will verify today and change res with less concentration. Or I’ll add pH’ed water to dilute. That works too, yeah?
62% rh
73.6 F
it fluctuates, but that’s the median.
Added ph’ed water and got ec to 1.6. It was 2.1
The ppm reads 720 @0.5 now.
They are in auto parts. Will the kind of flush themselves and re-uptake what they need? I know you can’t wash an auto pot because the salts are all at the top.
Hopefully, they bounce back.
73.6 F
it fluctuates, but that’s the median.
Added ph’ed water and got ec to 1.6. It was 2.1
The ppm reads 720 @0.5 now.
They are in auto parts. Will the kind of flush themselves and re-uptake what they need? I know you can’t wash an auto pot because the salts are all at the top.
Hopefully, they bounce back.
At 74 and 62, your grow is a little cold and the RH is a little high.
The best site for VPD I've found is here. VPD is like "feels like" for humans. From the picture below, at 74 and 62%, your "vapor pressure deficit" is about 0.9. VPD is the "vapor pressure deficit" between the inside of the leaf and the air outside the leaf. A leaf is full of water, the air next to it isn't so the water in the leaf is at higher pressure and will tend to move to the outside which is at lower pressure. The difference is the "deficit".
A higher difference//a higher deficit means that the plant will emit water, via transpiration, faster than if the deficit was lower.
One reason why you've been able to run higher EC is that the deficit is only 0.9x. As cannabis plants get older, they do better with higher VPD values. Seedlings like 0.8 - hot and moist but, going into flower, you should be at 1.2 and then move higher during flower.
The two images are a VPD chart from Pulse, one for veg, one for flower. They show the different optimal ranges for the two phases of growth and, at 74 and 62, you're at 0.9X it looks like which is a bit low for veg but, if you check the flower range, you're well out of optimal.
Ideally, you would have gone through veg at temps up to the mid-80's but that was then, this is now. At the higher temperature, you would have had even more vegetative growth but you're doing great at "only" at 74.
Now that you're moving into flower, 74° is an excellent temperature to ensure that you get the most secondary metabolites - THC and terpenes.
The issue that you should address is the RH. Per the VPD chart, you'd do best to get RH down by at least 10%. If you can bump the temperature a few degrees, that will help and you'll still be in good shape temperature-wise but dropping RH will help maximize your grow.
The core of the issue is that the moderate temp and higher RH (which is why VPD is low) means that your plant doesn't have to transpire much. That's one of the reasons why you've been able to run a high EC without nutrient issues - with transpiration being low, there's less water being taken up, which means that fewer ferts are being taken up.
Since you've dropped your EC but not lowered VPD, your plants will get fewer ferts so you might start to see some nutrient issues. Yup, it's all connected.
The priority would be to drop RH by about 10%. 74° is OK but dropping RH will not only improve how the plant grows, it will help reduce the chances of bud rot and it will help increase transpiration so your plant gets a higher level of chemicals coming in via transpiration.
The best site for VPD I've found is here. VPD is like "feels like" for humans. From the picture below, at 74 and 62%, your "vapor pressure deficit" is about 0.9. VPD is the "vapor pressure deficit" between the inside of the leaf and the air outside the leaf. A leaf is full of water, the air next to it isn't so the water in the leaf is at higher pressure and will tend to move to the outside which is at lower pressure. The difference is the "deficit".
A higher difference//a higher deficit means that the plant will emit water, via transpiration, faster than if the deficit was lower.
One reason why you've been able to run higher EC is that the deficit is only 0.9x. As cannabis plants get older, they do better with higher VPD values. Seedlings like 0.8 - hot and moist but, going into flower, you should be at 1.2 and then move higher during flower.
The two images are a VPD chart from Pulse, one for veg, one for flower. They show the different optimal ranges for the two phases of growth and, at 74 and 62, you're at 0.9X it looks like which is a bit low for veg but, if you check the flower range, you're well out of optimal.
Ideally, you would have gone through veg at temps up to the mid-80's but that was then, this is now. At the higher temperature, you would have had even more vegetative growth but you're doing great at "only" at 74.
Now that you're moving into flower, 74° is an excellent temperature to ensure that you get the most secondary metabolites - THC and terpenes.
The issue that you should address is the RH. Per the VPD chart, you'd do best to get RH down by at least 10%. If you can bump the temperature a few degrees, that will help and you'll still be in good shape temperature-wise but dropping RH will help maximize your grow.
The core of the issue is that the moderate temp and higher RH (which is why VPD is low) means that your plant doesn't have to transpire much. That's one of the reasons why you've been able to run a high EC without nutrient issues - with transpiration being low, there's less water being taken up, which means that fewer ferts are being taken up.
Since you've dropped your EC but not lowered VPD, your plants will get fewer ferts so you might start to see some nutrient issues. Yup, it's all connected.
The priority would be to drop RH by about 10%. 74° is OK but dropping RH will not only improve how the plant grows, it will help reduce the chances of bud rot and it will help increase transpiration so your plant gets a higher level of chemicals coming in via transpiration.
2.1 = 1100 but there's a reason why it was working well. Check my other posting.62% rh
73.6 F
it fluctuates, but that’s the median.
Added ph’ed water and got ec to 1.6. It was 2.1
The ppm reads 720 @0.5 now.
They are in auto parts. Will the kind of flush themselves and re-uptake what they need? I know you can’t wash an auto pot because the salts are all at the top.
Hopefully, they bounce back.
720 may be good but you're transpiration rate was a little low because of "low" temp + RH value = VPD on the low side, per my other posting.
Changed the res.
pH 5.8
ppm (500) 704
pH 5.8
ppm (500) 704
I am running a dehumidifier in my basement. I can reduce the RH. After the yellowing, will the plant still be able to produce quality buds?
Great, you've got a dehu. Check the image of the VPD chart that I sent. You're in early flower so you'll want to set a VPD of 1.2
VPD is the difference between the water "pressure" in the leaf and the water pressure in the surrounding air. To be calculated accurately, you need to know the temperature of the leaves. It will be different than the air temp…it should be different than the air temp.
Check out the pictures I posted of the VPD charts and you'll see that the "offset" (the difference between the two temperatures) is -2. That means that the leaf surface temperature (LST) is 2° lower than the ambient temp. That's a good working value but it'd preferable to get an IR thermometer ($25±) and get the actual value.
When there's a lot of air moving in the tent, the LST may be great than -2 and you should adjust temp + RH in face of that different value.
It's OK if you don't get the LST to the nearest degree. The big win is that you're getting it in the ballpark.
Re. yellowing - it looks like an Mg issue and, if you bring VPD in line, that should start to take care of it. The dead spots on leaves aren't coming back but having some leaves that are yellowing is, frankly, par for the course.
"quality buds" - absolutely. You've got a low % of leaves that are a symptom of a nutrient imbalance. There's a good chance that your VPD was off and you're dealing with that issue. You got tons of leaves and branches and that's where the buds forms so you're in good shape in terms of having a good foundation for the plant to build on.
I think it was @HydoDan who said to open up the canopy and that's a great point. Until at least a week from now, your plant is still building its structure (branches and leaves). Once it finishes build out, which is two weeks into flower, that's when you'll want to start looking at things "under the hood" that might block air flow. The plant will be more "open" but it's important to keep RH in the 50's and to ensure that you've got "lots of wind" moving in the grow environment.
Conventional wisdom says that leaves should be moving slightly - the common term is "rustling". Since I'm a skeptic and a long time software engineer (>30 years), I think in numbers and I've found a few references to 2 meters/second. $20 on Amazon got me an anemometer and I turned up the fans in my tent until the leaves were "rustling" and, you guessed it, wind speed was 2 meters per second.
The bottom line is that you were a bit wide of the mark on major parts of the grow environment - EC and VPD - but no biggie cause you've got great looking plants with a few bad leaves. One wag on You Tube said, paraphrasing, "there's nothing to worry about if you've got <30% of your leaves being yellow". That shocked me - I get squirrely waaay before that - but that statement came from someone who's been in the biz for many years so I've got to assume that he's know of what he speaks.
You shouldn't see a progression in the symptoms you're seeing (the yellowing leaves) with the change in RH and EC and the good thing is that at this stage of growth, things really start to take off.
The dehumidifier is way across a basement, and there’s no way to get it in the tent, sadly. I think in can still get the humidity down enough. Giving it a shot in the morning when I get up and go down my stair chair lol.Great, you've got a dehu. Check the image of the VPD chart that I sent. You're in early flower so you'll want to set a VPD of 1.2
VPD is the difference between the water "pressure" in the leaf and the water pressure in the surrounding air. To be calculated accurately, you need to know the temperature of the leaves. It will be different than the air temp…it should be different than the air temp.
Check out the pictures I posted of the VPD charts and you'll see that the "offset" (the difference between the two temperatures) is -2. That means that the leaf surface temperature (LST) is 2° lower than the ambient temp. That's a good working value but it'd preferable to get an IR thermometer ($25±) and get the actual value.
When there's a lot of air moving in the tent, the LST may be great than -2 and you should adjust temp + RH in face of that different value.
It's OK if you don't get the LST to the nearest degree. The big win is that you're getting it in the ballpark.
Re. yellowing - it looks like an Mg issue and, if you bring VPD in line, that should start to take care of it. The dead spots on leaves aren't coming back but having some leaves that are yellowing is, frankly, par for the course.
"quality buds" - absolutely. You've got a low % of leaves that are a symptom of a nutrient imbalance. There's a good chance that your VPD was off and you're dealing with that issue. You got tons of leaves and branches and that's where the buds forms so you're in good shape in terms of having a good foundation for the plant to build on.
I think it was @HydoDan who said to open up the canopy and that's a great point. Until at least a week from now, your plant is still building its structure (branches and leaves). Once it finishes build out, which is two weeks into flower, that's when you'll want to start looking at things "under the hood" that might block air flow. The plant will be more "open" but it's important to keep RH in the 50's and to ensure that you've got "lots of wind" moving in the grow environment.
Conventional wisdom says that leaves should be moving slightly - the common term is "rustling". Since I'm a skeptic and a long time software engineer (>30 years), I think in numbers and I've found a few references to 2 meters/second. $20 on Amazon got me an anemometer and I turned up the fans in my tent until the leaves were "rustling" and, you guessed it, wind speed was 2 meters per second.
The bottom line is that you were a bit wide of the mark on major parts of the grow environment - EC and VPD - but no biggie cause you've got great looking plants with a few bad leaves. One wag on You Tube said, paraphrasing, "there's nothing to worry about if you've got <30% of your leaves being yellow". That shocked me - I get squirrely waaay before that - but that statement came from someone who's been in the biz for many years so I've got to assume that he's know of what he speaks.
You shouldn't see a progression in the symptoms you're seeing (the yellowing leaves) with the change in RH and EC and the good thing is that at this stage of growth, things really start to take off.
They’re running on 20/4. I have a lux meter as well as photone for full spectrum led. At what lux/DLI do you think I should be? I raised the lights a bit since they were showing signs of light stress.
I cut off a few low thin branches, I thought I was supposed to do that at this point. You’re saying in 2 weeks? I only cut a few small ones, as you can see in the pic. Here’s hoping they don’t stall.
I can’t thank you enough for being so elaborate and for taking the time to help me.
Attachments
Getting a bit concerned. Unfortunately, the dehumidifier is cranking at Max, and the Rh in the tent is 57%. Looks like I’m at about 74°F. Over 24 hours, max is 75°, minimum is 70°.Great, you've got a dehu. Check the image of the VPD chart that I sent. You're in early flower so you'll want to set a VPD of 1.2
VPD is the difference between the water "pressure" in the leaf and the water pressure in the surrounding air. To be calculated accurately, you need to know the temperature of the leaves. It will be different than the air temp…it should be different than the air temp.
Check out the pictures I posted of the VPD charts and you'll see that the "offset" (the difference between the two temperatures) is -2. That means that the leaf surface temperature (LST) is 2° lower than the ambient temp. That's a good working value but it'd preferable to get an IR thermometer ($25±) and get the actual value.
When there's a lot of air moving in the tent, the LST may be great than -2 and you should adjust temp + RH in face of that different value.
It's OK if you don't get the LST to the nearest degree. The big win is that you're getting it in the ballpark.
Re. yellowing - it looks like an Mg issue and, if you bring VPD in line, that should start to take care of it. The dead spots on leaves aren't coming back but having some leaves that are yellowing is, frankly, par for the course.
"quality buds" - absolutely. You've got a low % of leaves that are a symptom of a nutrient imbalance. There's a good chance that your VPD was off and you're dealing with that issue. You got tons of leaves and branches and that's where the buds forms so you're in good shape in terms of having a good foundation for the plant to build on.
I think it was @HydoDan who said to open up the canopy and that's a great point. Until at least a week from now, your plant is still building its structure (branches and leaves). Once it finishes build out, which is two weeks into flower, that's when you'll want to start looking at things "under the hood" that might block air flow. The plant will be more "open" but it's important to keep RH in the 50's and to ensure that you've got "lots of wind" moving in the grow environment.
Conventional wisdom says that leaves should be moving slightly - the common term is "rustling". Since I'm a skeptic and a long time software engineer (>30 years), I think in numbers and I've found a few references to 2 meters/second. $20 on Amazon got me an anemometer and I turned up the fans in my tent until the leaves were "rustling" and, you guessed it, wind speed was 2 meters per second.
The bottom line is that you were a bit wide of the mark on major parts of the grow environment - EC and VPD - but no biggie cause you've got great looking plants with a few bad leaves. One wag on You Tube said, paraphrasing, "there's nothing to worry about if you've got <30% of your leaves being yellow". That shocked me - I get squirrely waaay before that - but that statement came from someone who's been in the biz for many years so I've got to assume that he's know of what he speaks.
You shouldn't see a progression in the symptoms you're seeing (the yellowing leaves) with the change in RH and EC and the good thing is that at this stage of growth, things really start to take off.
Regarding the lights, I’m not sure what I’m supposed to be running them at. I have a lux meter, and Photone. I really don’t want these plants to waste away. It’s happened to me before. I’ve tried organic, Hydro, promix, and now auto pot. It must be me, and if this one fails, I think I might just hang it up because it’s just too frustrating. I don’t know what I keep doing wrong.
Attachments
@Delps8Great, you've got a dehu. Check the image of the VPD chart that I sent. You're in early flower so you'll want to set a VPD of 1.2
VPD is the difference between the water "pressure" in the leaf and the water pressure in the surrounding air. To be calculated accurately, you need to know the temperature of the leaves. It will be different than the air temp…it should be different than the air temp.
Check out the pictures I posted of the VPD charts and you'll see that the "offset" (the difference between the two temperatures) is -2. That means that the leaf surface temperature (LST) is 2° lower than the ambient temp. That's a good working value but it'd preferable to get an IR thermometer ($25±) and get the actual value.
When there's a lot of air moving in the tent, the LST may be great than -2 and you should adjust temp + RH in face of that different value.
It's OK if you don't get the LST to the nearest degree. The big win is that you're getting it in the ballpark.
Re. yellowing - it looks like an Mg issue and, if you bring VPD in line, that should start to take care of it. The dead spots on leaves aren't coming back but having some leaves that are yellowing is, frankly, par for the course.
"quality buds" - absolutely. You've got a low % of leaves that are a symptom of a nutrient imbalance. There's a good chance that your VPD was off and you're dealing with that issue. You got tons of leaves and branches and that's where the buds forms so you're in good shape in terms of having a good foundation for the plant to build on.
I think it was @HydoDan who said to open up the canopy and that's a great point. Until at least a week from now, your plant is still building its structure (branches and leaves). Once it finishes build out, which is two weeks into flower, that's when you'll want to start looking at things "under the hood" that might block air flow. The plant will be more "open" but it's important to keep RH in the 50's and to ensure that you've got "lots of wind" moving in the grow environment.
Conventional wisdom says that leaves should be moving slightly - the common term is "rustling". Since I'm a skeptic and a long time software engineer (>30 years), I think in numbers and I've found a few references to 2 meters/second. $20 on Amazon got me an anemometer and I turned up the fans in my tent until the leaves were "rustling" and, you guessed it, wind speed was 2 meters per second.
The bottom line is that you were a bit wide of the mark on major parts of the grow environment - EC and VPD - but no biggie cause you've got great looking plants with a few bad leaves. One wag on You Tube said, paraphrasing, "there's nothing to worry about if you've got <30% of your leaves being yellow". That shocked me - I get squirrely waaay before that - but that statement came from someone who's been in the biz for many years so I've got to assume that he's know of what he speaks.
You shouldn't see a progression in the symptoms you're seeing (the yellowing leaves) with the change in RH and EC and the good thing is that at this stage of growth, things really start to take off.
this doesn’t look great. I need help. Buds are forming, as are trichomes, but I’m a little concerned with the darkening/spots/yellowing, etc.
anything I can do to improve, or do you think it’s going okay?
