Grow light - Which is better?

[neewbiedoobie]

Could you use a LED shop light to grow seedlings and clones ? It is 49 watts with 4800 lumens and 4200k. Or would a T12 cool white 40 watt be better for starting plants? Thanks for all replies and looking forward to all the input.

 

[neewbiedoobie]

Could you use a LED shop light to grow seedlings and clones ? It is 49 watts with 4800 lumens and 4200k. Or would a T12 cool white 40 watt be better for starting plants? Thanks for all replies and looking forward to all the input.

Wow, 200 and some people checked this thread out and no replies.... It also says that this LED shoplight is equal in brightness to 3-32 watt T-8S. Hopefully someone can reply to this thread and give me some insight... Thanks

 

[LEDBud]

The 4200k LED tube would be my choice , I think you should do tests and post the results. I vote the LED will grow the seedlings larger faster.

I have used and hate T8's and t5's , some people like them / use them

 

[jhfhklsnhfldk]

My Experience, so far, is that CFLs and Fluoro tubes will grow the plants to a MUCH larger size in their first 3-4 weeks than an LED will. After that the LEDs take over and perform much better in flower.

 

[LEDBud]

edot: I find led's to win in both situations , I have always had poor growth with Tubes for one reason or another

 

[jhfhklsnhfldk]

The first 2 pics are day 14 under a combination of CFL and Fluoros kept about 2-4" from the plants. The third pic is from today, day 15 under LEDs kept 30" above.

I will also try to add a link below to a cool post in the "grow light" forums here under "grow room".

Year-long study of LED greenhouse lighting yields illuminating results

Go to the bottom and check out the video.

After this grow, I hope to be able to verify that plants grow slower under LED lights but produce stronger plants and better buds.

 

[sshamish]

Cool experiment!


Sent from my iPhone using 420 Magazine Mobile App

 

[LEDBud]

Here's my last two plants grown with a LED panel , they are just over 3 weeks from germination in the photo

in 12 inch Terra Cotta pots

 

[jhfhklsnhfldk]

Here's my last two plants grown with a LED panel , they are just over 3 weeks from germination in the photo

in 12 inch Terra Cotta pots

These are mine at 23 days in 3 gallon fabric

 

[LEDBud]

those plants look real nice , good job and nice to see !

 

[jhfhklsnhfldk]

Thanks.

I do notice though that even with the CFLs and Fluoros that close to the plants, that they still stretch more than my LEDs 30" above. From everything I've seen and read, LEDs will start off slower but end up with better yield.
I am growing autos, which is the only reason I care about their size at the 3 week point. The bigger I can get them before they start preflower the better the yield I should get.

The internodal stacking is supposed to be much tighter with LED and so far it looks to be true. I would never go back to CFL or fluoro but I don't regret the experience. They are a total pain in the ass and give you no room to work.

 

[LEDBud]

Not sure why you are using 30 inches its much to high IMO it will give weaker results then if used closer.

I used 12 inches from the seedling stage onward and got 8 Oz from a auto last grow. The growth gets explosive at 8 to 12 inches.

Give it a try , move it to 18 inches for a week then to 12 inches for faster growth. IMO 18 inches is the maximum distance you should use.

As the lights intensity/ lumens drops by half about every 12 inches , a 175w led panel at 30 inches is putting out about 50 watts of effective light power.

 

[jhfhklsnhfldk]

Thanks for the tip. It's hard to find good info about this. I have a 1200w (540 actual) and 2-300w (140 actual) hanging over them now. This won't burn them will it?

I am going to move them to 18" right now. I definitely want them to be much bigger at 3 weeks.

Thanks again

 

[LEDBud]

I suspect they will erect their leavers at 18 inches in happiness , at 12 inches from the get go they may lower the leaves a bit but it may burn them ,its best to acclimatize them to it somewhat slowly.

They seem to droop the leaves to ward off excess light when its too strong.

Make sure your using a cal mag supplement and remember the plants will get hungrier / need more nutrients with the lights kept closer , Everything speeds up water consumption food growth

don't over feed them to be nice though .. the plants are sensitive to overfeeding , try to keep them from being deficient more then loaded with excess nutrients.

i think you will do fine with the lights up close , your doing good so far

 

[neewbiedoobie]

Thanks for all of the replies... Nice looking plants you have there

 

[neewbiedoobie]

Oh, and how many hours of light are you giving your autos?

 

[LEDBud]

Not sure who you are directing that at probably me , I basically used 24hrs , well I started with 18hrs and moved it to 20 on 4 off then 24 on.

I suggest to give them 20 on 4 off but its really not needed. People think that plants need the lights off to do the sleep cycle , but they would be mistaken.

As the plants will shift into the night cycle metabolic mode when it needs it lights on or lights off.

You may find the plant does better with some lights off time , then again if your light energy is low they may well do better with 24hrs on light hours.

I got 8 Oz off a auto last grow and a 2 Oz and 3 Oz bud off two Auto clones using mostly 24hrs on.

Yep , you can clone autos , check out the Jock Horror link below in my signature

 

[neewbiedoobie]

Not sure who you are directing that at probably me , I basically used 24hrs , well I started with 18hrs and moved it to 20 on 4 off then 24 on.

I suggest to give them 20 on 4 off but its really not needed. People think that plants need the lights off to do the sleep cycle , but they would be mistaken.

As the plants will shift into the night cycle metabolic mode when it needs it lights on or lights off.

You may find the plant does better with some lights off time , then again if your light energy is low they may well do better with 24hrs on light hours.

I got 8 Oz off a auto last grow and a 2 Oz and 3 Oz bud off two Auto clones using mostly 24hrs on.

Yep , you can clone autos , check out the Jock Horror link below in my signature

Thanks for responding... I checked out the jock horror and they look real nice.. thanks

 

[Guano]

I just installed these same shop lights above my workbench last Friday. It feels like I installed a sky light even though I'm in the basement. The first thing I thought of was using a few more of these lights for seedlings or clones, so I may set something up on the workbench to test.

I'm interested to see how these work out for you.