18 or 24 hours of light

[Dr. D]

Which is best fot u guys i always use 24 hours light for veg, but i recently read some where that some plants afghanis or pure indicas grow faster under 18 and i had my shit (indica) under 18 for a short while then they went to 24 and im sure the growth slowed in 24...any feed back on how you guys ( and gals) do it wud be a great help as we all want the fastest growth ..

 

[Joemutt1978]

I would say 18,

I always give my veggers a little dark, not on a timer or anything, usually just cut off the lights on my lunch break, and cut them back on when I get home, that is the hottest part of the day so the lights are off.

I think that something happens when they are in the dark, hormones or something, but it is good, they need dark I think. On younger ones you can see yellow leaves right when you cut on the lights, these are all new growth. It happens alot quicker in the dark, I have found.

Good Luck.

 

[The Hashasin]

18 or 24?

18 or 24?

Hiya Doc,
I'm now a converted 18/6 man. I used to use 24 hr HPS with 5% blue. I have upped my lumens since from 250 for 400W and going 650 for flower. I am convinced since growing the same species for 4th time that the 18/6 is the best. There seems to be more spurt of growth over night and the plants color has remained a healthy green, not the dark green I was experiencing with 24hr regime in veg. Hope that helps some, they definalty need time to photo synth...

 

[Guest]

High Dr D. I have read that a plant can only process 16-18 hrs of light per day efficiently. After that, a point of diminishing returns is reached and the electricity is used inefficiently. I got that from Jorge Cervantes book "Indoor Marijuana Horticulture". Hope this helps. peace

 

[ezozo]

I am using 24/0 with out any problem (400MH) but I think I will try 20/4 or 18/6.
It will be nice to hear some experienced grower.

Thank's Hashasin for you imoput..
peace
zozo

 

[badmf]

With this you have a choice, 24 will grow faster than 18/6 as the plant "light" activities utilise photosynthesis at a higher rate than including a dark cycle. But there are advantages to having a "nite", as root development is increased and plant "light" cycles are set, otherwise the plant sees only one long azz day instead of many, which if from seed will cut back its maturity. Most plants need at least 2-3 months to fulfill their potential so to do anything that would shorten this will cut from its potency and yeild development. Answer is go 24 for a couple days then 18/6 from seed and clone after 2-3 months minimum. Without going into scientific detail, the processes the plant goes through while dark are beneficial.

 

[Californian]

not 24

not 24

Use 18/6. Photosynthesis involves both light and dark cycles, look up the "Krebs cycle" if you really want to read more.

 

[dowink]

I always start out at 20 hrs until the leaves with 5 sets start forming. Then switch to 24 hrs. This seems to always give me more females.

 

[So Quick]

I don't think 24/0 justifies the extra electricity and wear and tear on your ballast...I've never done a side by side of the 2, but I have vegged in both...and I prefer to go 18/6...

SQ

 

[herouana]

good question and answers now i don't have to ask.

 

[Dr. D]

awesome response

awesome response

Thanks for ur input evryone im gonna go 18/6 now .thanks

 

[Harry Gypsna]

use 18/6 if ur timers r reliable, its better to give em some "down time" to use the food theyve taken in if u get me.Its more natural too

 

[Rumpleforeskin]

18/6 is great if you don't mind growing your weed slower.

 

[SSH]

24/0 for first week or two to get a jump on growth then switch to 18/6.

 

[chubbynugs]

24/0 for first week or two to get a jump on growth then switch to 18/6.

Why not also have that jump in growth after that first week or two? I am all about the 24/7 schedule especially since i pull nugs like this in my veg closet.Masterlow

 

[GHETTO_grower]

pretty sure 18/6 shows the sex faster

 

[bugbud63]

I like 24/0 for 1 week under 4' shop light ,then 18/6 when using hid lights or CFL's.Whats funny is if i use cfl's from the start they dont grow very well at all,until about 1 week old,the shop light is much faster(just a reg 4' shop light).I believe its becase of too much heat from the cfl's which in turn drys the soil very fast and can burn them;I keep 27 watt cfl's about 1'' from tops.Good Luck.Stay Safe!!

 

[HeadyPete]

If I don't use 24 hr light my LUI mom will flower. They like to autoflower and will under anything less than 24hr.

 

[WaywardBob]

pretty sure 18/6 shows the sex faster

3 of my 5 plants showd sex in 20 days from seed under 24/0.. i thnk thats pretty good isnt it? maaybe i had to genetics, never gone 18/6 before tho..

 

[facelift]

I read somewhere that plants need 1-2 hours of dark to improve photosynthisis.