18/6 and 24 hour on and off?

[TANKJR]

I've played with light times/timing quite a bit and here's what I have observed...24/7 can be a little expensive when using HID lighting, with CFL and Flouros, it makes very little difference in my electric bill at all no matter how much I run them, so I run them 24/7, this is for veggin. If you start at 24/7 and then work down on the light side half hourly or hourly until you get to 12/12, you just wasted a week or more imo, unless you've got a particularly sensitive strain. I grow AK47 and it doesn't seem to care much. If you go with 18/6 or 20/4 and switch for the duration of veggin, it doesn't matter...in veg mode the plants are generally more forgiving to light time changes. In flower mode they are not so forgiving, so get to 12/12 from whatever as fast as possible, I change bulbs and times overnight and go straight to 12/12 for two weeks to insure they get the message to flower and then go to 13/11 until done. I would not recommend noobs jumping, (and try to never go backwards!) around your light times during flowering, but in veg mode, it doesn't seem as critical...hope this helps!

An hour or less here and there doesn't seem to matter in either mode, (I have forgotten to close doors, or whatever to screw up a light cycle myself before) but make sure the dark time in flowering is truly dark and uninterrupted! Think about the outdoors grower and his plants...they see cloudy days, rainy days, bright sunny days, and moonless or moonlit nights....everything still happens, veggin, flowering and budding, but it takes the plant longer to do it. In the interest of efficiency (or speed of growth, which we assume is as fast as possible), I would not be changing things back and forth too much. The less stress, the faster the success with MJ, as far as lighting goes and too much change, makes too much stress, slowing the whole thing down.

IMO, the time for experimenting with light times is not in the middle of a grow, but planned from the beginning. Pick a number and stick with it as much as possible throughout the grow...you'll only slow things down changing things up in the middle of a cycle, (unless ADDING more lights) and you may not realize any significant saving on your electric bill either, and you may not be able to tell if what you change makes any difference or not, and then won't you feel silly because you did all these changes and you won't know whether you made any difference or not, or saved anything or not?

Personally I don't think you'll save more than a few cents between the two times you speak of with anything except high wattage HIDs (MH or HPS).

TANKJR Reviewed by TANKJR on 11-23-2010. 18/6 and 24 hour on and off? Hey guys, im just curious if it would screw anything up or damage or whatever to my plant if i were to do 18/6 one day and then the next 2 days the 24 hour method and then after that back to 18/6 .....etc. and the reason i ask this is cause i want to do 24/7 but it would still be to much electricity for me to use even tho im using cool white t12 florescents, and want to get the most i can so i figured one day 18/6 and the 2 days 24.....thanx for reading and please get back to me soon fellow Rating: 5

[Slevinkal]

then go to 13/11 until done.

You claim this is better that 12/12?

[TANKJR]

I've played with light times/timing quite a bit and here's what I have observed...24/7 can be a little expensive when using HID lighting, with CFL and Flouros, it makes very little difference in my electric bill at all no matter how much I run them, so I run them 24/7, this is for veggin. If you start at 24/7 and then work down on the light side half hourly or hourly until you get to 12/12, you just wasted a week or more imo, unless you've got a particularly sensitive strain. I grow AK47 and it doesn't seem to care much. If you go with 18/6 or 20/4 and switch for the duration of veggin, it doesn't matter...in veg mode the plants are generally more forgiving to light time changes. In flower mode they are not so forgiving, so get to 12/12 from whatever as fast as possible, I change bulbs and times overnight and go straight to 12/12 for two weeks to insure they get the message to flower and then go to 13/11 until done. I would not recommend noobs jumping, (and try to never go backwards!) around your light times during flowering, but in veg mode, it doesn't seem as critical...hope this helps!

An hour or less here and there doesn't seem to matter in either mode, (I have forgotten to close doors, or whatever to screw up a light cycle myself before) but make sure the dark time in flowering is truly dark and uninterrupted! Think about the outdoors grower and his plants...they see cloudy days, rainy days, bright sunny days, and moonless or moonlit nights....everything still happens, veggin, flowering and budding, but it takes the plant longer to do it. In the interest of efficiency (or speed of growth, which we assume is as fast as possible), I would not be changing things back and forth too much. The less stress, the faster the success with MJ, as far as lighting goes and too much change, makes too much stress, slowing the whole thing down.

IMO, the time for experimenting with light times is not in the middle of a grow, but planned from the beginning. Pick a number and stick with it as much as possible throughout the grow...you'll only slow things down changing things up in the middle of a cycle, (unless ADDING more lights) and you may not realize any significant saving on your electric bill either, and you may not be able to tell if what you change makes any difference or not, and then won't you feel silly because you did all these changes and you won't know whether you made any difference or not, or saved anything or not?

Personally I don't think you'll save more than a few cents between the two times you speak of with anything except high wattage HIDs (MH or HPS).

[TANKJR]

I claim nothing yet....this is the first time on that particular light schedule. We shall see and I will let everyone know if it made any difference or not. I read/spoke/saw a video (can't remember! LOL) somewhere that someone else uses this light schedule and gets somewhat bigger better buds, so I'm trying it out. I think he said he still does the two weeks of 12/12 to get it into flower mode, but it may be 13/11 throughout flowering. I am in day 26 of flowering, so it's too early to tell at this point, but I'm hoping for slightly bigger better myself! Some strains will not flower, or are very slow to flower on 13/11, so I have not tried the 13/11 on them yet...currently have AK47, and it seems to like it.

[TANKJR]

hmm, don't know why that one post got on here twice....????

[Slevinkal]

I claim nothing yet....this is the first time on that particular light schedule. We shall see and I will let everyone know if it made any difference or not. I read/spoke/saw a video (can't remember! LOL) somewhere that someone else uses this light schedule and gets somewhat bigger better buds, so I'm trying it out. I think he said he still does the two weeks of 12/12 to get it into flower mode, but it may be 13/11 throughout flowering. I am in day 26 of flowering, so it's too early to tell at this point, but I'm hoping for slightly bigger better myself! Some strains will not flower, or are very slow to flower on 13/11, so I have not tried the 13/11 on them yet...currently have AK47, and it seems to like it.

Hell ya! Keep us posted when you tally the results...

[PhatJay]

Instead of switching between 18/6 and 24/0 why not just do 20/4?

[Douglas1]

Instead of switching between 18/6 and 24/0 why not just do 20/4?

Damn, beat me to it :P was going to suggest 20/4 or 22/2...

[TANKJR]

I see no reason not to, other than efficiency...you could do 21/3 or whatever, but if your going for maximum growth in the shortest time, why would you? If the plant can take 24/0 light for weeks at a time with no apparent ill effects and growth is proportionate to the additional light/time AND you're using little additional electricity...why not use it? You could maybe get them to veg with only 14 or 15 hours too, but why would you? Just conversing here...comments?

[bullyslayer]

im using cool white t12 florescents,

these lights are only good for seedlings and rooted clones up to about 6" tall you need to switch to HID's, t8's,t5's, or cfl's after that.if you keep some 23 watt 6500k cfl's burning 18/6 your plants will stay in veg. you can then turn on a HPS in the middle of this cycle for a few hours to get good growth while saving on your ele bill.think of it as bright midday sun.