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24 on or 18/6 on off

Lacroix

Member
My seeds sprouted under 600 mh going 24 on. Is 24 on or 18/6 on off better? Other than energy savings. Also will it hurt to go to 18/6 from 24 on?
 

HatchBrew

Active member
Veteran
T5 or 250 for seeds. Twenty on for off is what I like. Plants do work in light and dark both are important. Depends a little on strain, sativa you could run on fifteen hours of light, whereas that might trigger photo sensitive plants
 

firehound

Member
18/6 imho is best for any plant to have a dark period. Builds roots while dark better. Also lots better for the power bill.600w is costing too much on smaller plants, may also stunt them until a bigger root mass grown. Small increasing steps up to that wattage is recomended. firehound:bump:
 

Lacroix

Member
I'm feeling unless your going to move your plants from inside to outside veg should be 24 on. Apparently this stresses them less if you move them out due to the night temps...
 

there goes edro

Well-known member
Veteran
18 on and 6 off works for me! Also seems to cut down on stretch and promotes quicker flowering. Just putting in my two cents, someone lend me a dollar!!!
 
S

SPG*

18/6. Plants are live and need to sleep man.so Obvious right from the start of growing.
They tell you when they have had enough light I.e the leaves go droopy (many varieties)
To keep the lights on! Cruel and NUTS.
:smoke:
 

TheCleanGame

Active member
Veteran
10 years ago I used 24/0 exclusively... now I give them a few hours to sleep and they show me their appreciation for it.

Keep it Clean! :D
 

stickshift

Active member
18/6. Plants are live and need to sleep man.so Obvious right from the start of growing.
They tell you when they have had enough light I.e the leaves go droopy (many varieties)
To keep the lights on! Cruel and NUTS.
Plain dumb tbh. :D

Anything that can prove plants need some dark time? I have kept plants in both conditions and don't find they beg for lights out... plants adapt... it's all to do with the circadian clock (body clock), I think I'm right to say this clock helps to control the auxin levels... whats far worse for the plant and stress is tweaking the light regime, but they will be fine with 24/0 if they are used to it.

If we grow indoors we're merely playing with plants responses to our advantage.. the only response I see benefit from with the lights out is when I want to trigger flowering.

The temp will play a part as much as the light will IMO.

http://docs.lib.noaa.gov/rescue/mwr/048/mwr-048-07-0415b.pdf

http://www.plantcell.org/content/18/4/792.full#sec-7

I personally don't feel they need much sleep, maybe I'm dumb!
 

Jhhnn

Active member
Veteran
My limited experience is that seedlings thrive on warmth & light, so I just use 24/0 to start. Once seeds are up & established, I up pot from 5 oz to 16 oz, go to 18/6. When they're a little taller than the solo cups, I up pot again to #1 nursery pots, continue veg, then up pot again to #3's when I go to 12/12.

With Colorado plant count restrictions, it seems important to use strong lighting to shorten the veg phase, get better yield over time.
 
S

SPG*

Many Varieties means a lot of strains but NOT all.
Maybe you have had the strains that don't tell you WHEN Sufficient amount of light has been achieved ?


Yeas after thought was "some" would find the last words offensive and not look AT THE CONTEXT of the Post I shall Amend things as you no doubt won't be the last.Real "full time angst lookers" will look at your quoting of me. Oh well..
And here ppl smoke weed.. Phuack :D

Pics are worth more than words! Biggrin mustn't mean anything here...
 

farmari

Member
18/6 or 24/0 or 20/4 all work well. Personally I like 20/4... sometimes 24/0 if environmental conditions ask for it (if the lights off temp would be too low, for example)
 
You can use a 600 to sprout seeds, you just don't need it right up on top of them. Start minimum 3' away from medium/propagator and slowly decrease as plant grows.

My 1 week old seedlings are about 18" away from a 600w MH and loving it.

I am a strong believer in dark periods. I think 24hrs of light is stressful to plants, it would be stressful to me, lol.

I like 20/4 through most of veg and 18/6 two weeks prior to switching to 12/12.
 

frankenstein2

Astronaut Status
Veteran
I run my veg at 18/6. That's in the set-up I have now. If needed I have run them at 24/0. That was strictly for the heat from a 400 hps. Burning a 400 watt light was a lot cheaper than a 1500 watt oil heater. Plus I could use the light from the light. Heaters don't put off much light.:biggrin:. I'm also a firm believer that plants need a dark period. But.....when circumstances dictate you do what you need to do.
 
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