[oldblue]

Hey all, I'm 1 week into vegging with my 6 lil VISC Sin clones and right now I have my 400mh light on them, vertically, in my 4x4 tent. I'm getting ready to redo my tent, and stack my 600hps on top of the 400mh(both in cooltubes). So, my question is, when would you turn the 600hps on? I usually just veg for 4-5wks with JUST the 400mh and then when i switch to flowering, i turn the 600 on as well. But i was wondering if it'd be beneficial to turn the 600 on during veg also(although the babies are only about 8-10" tall, so they'd be 2-3' under the 600)? Any thoughts??? If it wouldn't be a decent yeild booster, i'd rather save the $ and leave it off for now.

[hoosierdaddy]

The veg stage seems to be the stage that the plant uses what light it gets the most efficiently. You can get real decent results vegging with minimal clf's, where the same lighting in flower would be quite lacking.
And it always seems to me the best looking veg comes from blue light spectrum.
If it were me, I would hold off on the hps until flower and save coin.

[Mr Celsius]

Photosynthesis is based on multiple factors: light, temp, humidity, co2, oxygen in the root zone and availability of proper nutrients.

A plant can only grow as fast as its limiting factor.

Only you can answer your question: Is light the limiting factor or is something else?

[oldblue]

Originally Posted by Mr Celsius

Photosynthesis is based on multiple factors: light, temp, humidity, co2, oxygen in the root zone and availability of proper nutrients.

A plant can only grow as fast as its limiting factor.

Only you can answer your question: Is light the limiting factor or is something else?

Well, i guess there's really NO limiting factor. The temps are 72(lights on) and 66-68(lights off), humidity ranges from 30-50% in veg, each plant is in a 5gal DWC with a huge airstone that produces alot of O2, and I'm using Floranova, Liquid Karma and Calmag, with RO water. And the plants grow nice under just the 400mh. I just wondered if it'd be beneficial to add the HPS during veg? I've always JUST used the MH with great results. I just didn't want to waste the money of 600 more watts for the next month, if it's not gonna boost the yeild or quality significantly.

[Mr Celsius]

Originally Posted by oldblue

Well, i guess there's really NO limiting factor. The temps are 72(lights on) and 66-68(lights off), humidity ranges from 30-50% in veg, each plant is in a 5gal DWC with a huge airstone that produces alot of O2, and I'm using Floranova, Liquid Karma and Calmag, with RO water. And the plants grow nice under just the 400mh. I just wondered if it'd be beneficial to add the HPS during veg? I've always JUST used the MH with great results. I just didn't want to waste the money of 600 more watts for the next month, if it's not gonna boost the yeild or quality significantly.

Aside from your temps being a little low (I suggest 76-78, if you want to know why ask), then you will have a quicker veg with a full spectrum.

So finally its up to: veg faster VS the cost to do it. Is there some urgency to finishing within a certain time?

[oldblue]

Originally Posted by Mr Celsius

Aside from your temps being a little low (I suggest 76-78, if you want to know why ask), then you will have a quicker veg with a full spectrum.

So finally its up to: veg faster VS the cost to do it. Is there some urgency to finishing within a certain time?

I'm confused on the "veg faster" part. I was planning to veg about 5wks total, either way. Can u please explain what you mean by that? And yes, i'd like to know more about why you suggest 76-78. So, are you saying to add the HPS during veg, to get the full spectrum and the 78-80*?

Ps. I've always had too high temps(85-88). That's why i thought the lower temps(70-72) where ideal.

[oldblue]

Also, what's everyone's thoughts on the 400mh & 600hps during flower for a full spectrum, compared to a 400hps & 600hps in flower? My goal is to have the best yield of tight buds.

[Mr Celsius]

Originally Posted by oldblue

I'm confused on the "veg faster" part. I was planning to veg about 5wks total, either way. Can u please explain what you mean by that? And yes, i'd like to know more about why you suggest 76-78. So, are you saying to add the HPS during veg, to get the full spectrum and the 78-80*?

Ps. I've always had too high temps(85-88). That's why i thought the lower temps(70-72) where ideal.

Well, from what you have told me, your systems limiting factor is light. So if you add more light, your plants will grow at a faster rate. So maybe you want your plants to grow 4' tall, it usually takes you 5 weeks, but by adding the 600w, you might get to your goal in... who knows maybe 3 weeks. Most people don't just veg for a set amount of time, they veg for a goal of height/size and increasing the light maybe shorten the time of reaching that goal.

Plants have a vascular system just as humans do... all beit, not the same and not exactly for similar functions, but they do. This vascular system transports nutrients, glucose (the purpose of photosynthesis) and water throughout the plant. The more tugor (essentially water pressure) the plant has the efficiently it moves these components throughout the plant and speeds growth up. Cannabis has been shown to do very well at about 60-70% humidity and 78 degrees F. Lowering temperature slows the vascular system down and thus slows growth down.

So there's a sweet spot you can have your plants to make them happy, healthy and vigorous.

Simple idea of a plants vascular system:
https://en.wikipedia.org/wiki/Vascular_tissue

Temperature effects on nitrogen update:
https://www3.interscience.wiley.com/j...TRY=1&SRETRY=0

I hope all this helps you, if you have any questions, just ask.

[hoosierdaddy]

You know, a hobby grower can gt in 5-6 good harvest a year. Try it one way and then another and compare for yourself. You gotta weigh it all out, like MrC stated.
Do comparatives and compare everything including light bill costs.
If you chart everything you will end up with data that can tell you what way produced the most bud for the least coin.

[oldblue]

Originally Posted by Mr Celsius

Well, from what you have told me, your systems limiting factor is light. So if you add more light, your plants will grow at a faster rate. So maybe you want your plants to grow 4' tall, it usually takes you 5 weeks, but by adding the 600w, you might get to your goal in... who knows maybe 3 weeks. Most people don't just veg for a set amount of time, they veg for a goal of height/size and increasing the light maybe shorten the time of reaching that goal.

Plants have a vascular system just as humans do... all beit, not the same and not exactly for similar functions, but they do. This vascular system transports nutrients, glucose (the purpose of photosynthesis) and water throughout the plant. The more tugor (essentially water pressure) the plant has the efficiently it moves these components throughout the plant and speeds growth up. Cannabis has been shown to do very well at about 60-70% humidity and 78 degrees F. Lowering temperature slows the vascular system down and thus slows growth down.

So there's a sweet spot you can have your plants to make them happy, healthy and vigorous.

Simple idea of a plants vascular system:
https://en.wikipedia.org/wiki/Vascular_tissue

Temperature effects on nitrogen update:
https://www3.interscience.wiley.com/j...TRY=1&SRETRY=0

I hope all this helps you, if you have any questions, just ask.

Ahhh, now i understand. I'm going to try to dial my temps in to the high 70s then. I understand that the more light, the better and bigger growth as well. But, would the 600 be at all helpful, being 3' away? Since it's stacked on top of the 400, i wasn't sure. Maybe i should raise the buckets up for now, so they're even with the 400mh bulb, therefore the 600 would only be about 18-20" away from them???

Ps, i also just added a bucket of water to the tent, to bring RH up a bit. I live in the desert, so humidity is very low here.