Light timing for seedlings?

[reddiamond]

I am currently using a twin flourescent fitting over my seedling and it has its 1st pair of true leaves, the question i want to ask is should i run this 24/0 or is it better for the plant to run 18/6 as it's from seed?

 

[Indoor Sun King]

I leave my new seedlings under 24/0 from a few days to a week, then 20/4 or 18/6....but other prefer to veg 24/0....personal choice

 

[budfever]

24/0 or 18/6 is how I do it.
No real benefit of running 24/0 that I have seen.
But sometimes I still do it, like now as a matter of fact.

 

[dtowndabber]

Yeah I run my t5s over seedling 24/0 only cause I don't want to buy a timer. Then when they are ready to transplant it's 18/6.

 

[DeeTee]

18/6 for seedlings, then 20/4 for the rest of plants life.

 

[reddiamond]

So its purely down to personal preference and doesn't hurt the seedling, thats great, thx for the replies.

 

[greenlikemoney]

Hey, why not do a better thing? Go 12/12 from seed under the lower wattage CFL's ( used for flowering ) and in 3 weeks your plants will show their sex. At that time, kill any males, repot the females and put them back into veg ( veg lights and 18/6 or 24/0 ).....why wait 2 months only to realize you've been growing a plant with balls? I am always amazed to read posts here from people who have done everything right and then are disappointed their 2 months of hard work has produced failure. Hedge your bet, go 12/12 from seed. Read up on it and then ask yourself, "why am I risking my time, electricity, nutes etc etc to possibly be growing male plants'? Think about it.....

 

[MYOB]

Yeah I run my t5s over seedling 24/0 only cause I don't want to buy a timer. Then when they are ready to transplant it's 18/6.

How do you do 18/6 with no timer?

And I think 18/6 or 20/4 is better for plants, esp seedlings. They can only use so much light. The rest will be wasted, create excess heat and possible light saturation which is harmful.

 

[reddiamond]

They can only use so much light. The rest will be wasted, create excess heat and possible light saturation which is harmful.

How does light saturation harm the plant, what are the symptoms?

Hey, why not do a better thing? Go 12/12 from seed under the lower wattage CFL's ( used for flowering ) and in 3 weeks your plants will show their sex. At that time, kill any males, repot the females and put them back into veg ( veg lights and 18/6 or 24/0 ).....why wait 2 months only to realize you've been growing a plant with balls? I am always amazed to read posts here from people who have done everything right and then are disappointed their 2 months of hard work has produced failure. Hedge your bet, go 12/12 from seed. Read up on it and then ask yourself, "why am I risking my time, electricity, nutes etc etc to possibly be growing male plants'? Think about it.....

Thanks for the tip but I use feminized seeds

 

[Novicehomegrower]

i veg 24/0 under t5s then 18/6 for a couple weeks then bloom. i did that last time and im going to stick with it . the plants sleep 4 hours by themselves even with 24/0 so there is nothing wrong with leaving it on all the time

 

[Novicehomegrower]

depends if your running a HID i wouldn't leave a HID on for 24 hours just for the cost's to run it

 

[whitnasty1]

Personal preference really, I wouldn't go below 18/6 however.

 

[reddiamond]

depends if your running a HID i wouldn't leave a HID on for 24 hours just for the cost's to run it

Its only a week old so its under a 2 foot shop flourescent with a daylight 865 bulb and currently 24/0 but i think tomorrow i'm gonna get a timer and set it for 20/4 so it gets some rest.

 

[MYOB]

you want to reach the "light compensation point" where the rate of photosynthesis matches the rate at which the plant can use that energy for growth(respiration). Plants use oxygen along with energy from photosynthesis for respiration. They take oxygen from the leaves and roots through a process called transpiration. When light saturation point is reached, transpiration rate exceeds respiration rate. This leads to problems with the plants ability to properly use nutrients as well as its ability to maintain balance in fluids. The leaves also lose their ability to cool themselves via transpiration and the often excess heat that accompanies light saturation becomes harmful to plant health.