Too much light for seedlings (uncapped LED bulbs)

Mass Medicinals

Mass Medicinals

Well-Known Member
Hi All,

Our seedlings are growing very slowly. Could we have too much Cree LED light on them?

the lights are about 12 inches above the tops of the seedlings. Twelve 60w (9w equivalent) uncapped bulbs in a 3x4 grid pointing straight down on the seedlings.

There is a 6 inch fan blowing air when the lights are on.

Best guess the air temp is probably high 70's. No idea about humidity at the moment (meter is still backlogged from Amazon)...
 
cannn

cannn

Well-Known Member
Mass Medicinals said:
Hi All,

Our seedlings are growing very slowly. Could we have too much Cree LED light on them?

the lights are about 12 inches above the tops of the seedlings. Twelve 60w (9w equivalent) uncapped bulbs in a 3x4 grid pointing straight down on the seedlings.

There is a 6 inch fan blowing air when the lights are on.

Best guess the air temp is probably high 70's. No idea about humidity at the moment (meter is still backlogged from Amazon)...
Click to expand...
Hard to comment without a pic

And info on how old they are
 
Mass Medicinals

Mass Medicinals

Well-Known Member
Working on photos our camera is not the best at seedling cameos. Medium roots organics soilless coco mix. No nutrient feeding at this time just still water that has been sitting out for a couple days. 18/6 lighting schedule.

Age: 5 are a couple weeks old now (but were overwatered and we're trying to bring them back). The other 2 are maybe a week old.
 
  • Like
Reactions: gg2
Cx2H

Cx2H

Well-Known Member
Mass Medicinals said:
Hi All,

Our seedlings are growing very slowly. Could we have too much Cree LED light on them?

the lights are about 12 inches above the tops of the seedlings. Twelve 60w (9w equivalent) uncapped bulbs in a 3x4 grid pointing straight down on the seedlings.

There is a 6 inch fan blowing air when the lights are on.

Best guess the air temp is probably high 70's. No idea about humidity at the moment (meter is still backlogged from Amazon)...
Click to expand...
I'd back them off to 18-24 inches and see how they respond. I have a A19 and par31 light grow and that sheet is blinding so I imagine you are 4x brighter. I was getting burn from them around that height.

They pale green, no luster?
 
Mass Medicinals

Mass Medicinals

Well-Known Member
the two newer ones have the dark green leaves. Though they are bending slightly, they aren't reaching up for the light.

All of the ones that were nearly killed are light green.
 
  • Like
Reactions: gg2
Lordhooha

Lordhooha

Well-Known Member
Mass Medicinals said:
We're calling these Day 15. Not really sure at this point and the start of the month makes it easier for us. o_O

View attachment 3978395 View attachment 3978396 View attachment 3978397 View attachment 3978398 View attachment 3978399 View attachment 3978400 View attachment 3978401 View attachment 3978402 View attachment 3978403 View attachment 3978404
Click to expand...
Wow those look haggard man and small for 15 days. I start my seed under a thousand watts. Did you poke I
Holes in the bottom of the cups they look a bit over watered and sick.
 
  • Like
Reactions: gg2
Mass Medicinals

Mass Medicinals

Well-Known Member
The back row and the single front cup were part of a cohort that was overwatered in peet pellets. Around day 8 those were broken by hand out of the pellets and transplanted into pre-mixed coco. So we're really hoping that they will start to thrive given the watering is being better regulated and on an every other day cycle.

The middle row end cups are about half the age and appear to be doing well. Certainly have the better color to them and the leaves aren't drooping.

The cups have 4-5 large triangular cuts in them from scissors. We water in the morning every other day. Just try to pour it slowly and stop when we see run-off. The water is just tap that's been sitting out for almost 2 days. after watering the jug is topped off and allowed to sit till the next watering.

Basically given our very limited knowledge and still growing skill set. We would be more than happy if the middle row alone were to survive to a point where they could go under the 600 veg light. Really that's something we don't know when to transition over to. And likely a new thread.
 
  • Like
Reactions: gg2
Lordhooha

Lordhooha

Well-Known Member
Mass Medicinals said:
The back row and the single front cup were part of a cohort that was overwatered in peet pellets. Around day 8 those were broken by hand out of the pellets and transplanted into pre-mixed coco. So we're really hoping that they will start to thrive given the watering is being better regulated and on an every other day cycle.

The middle row end cups are about half the age and appear to be doing well. Certainly have the better color to them and the leaves aren't drooping.

The cups have 4-5 large triangular cuts in them from scissors. We water in the morning every other day. Just try to pour it slowly and stop when we see run-off. The water is just tap that's been sitting out for almost 2 days. after watering the jug is topped off and allowed to sit till the next watering.

Basically given our very limited knowledge and still growing skill set. We would be more than happy if the middle row alone were to survive to a point where they could go under the 600 veg light. Really that's something we don't know when to transition over to. And likely a new thread.
Click to expand...
You can now just keep the light up high. I keep mine at 24" from seedlings watering every other day seem a bit excessive that's a lot of space that to hold extra water. The roots soil your using isn't bad I generally mix that with green fields and pro mix when I I'm not using supersoil. Just watch the amount of water your giving them and you should be good for a week or two. Just watch them and water them when they ask you trust me you'll learn to read your plants just be patient.
 
  • Like
Reactions: gg2
Mass Medicinals

Mass Medicinals

Well-Known Member
Oh wait. No way!!!!!

We just figured out what 20% run-off means. Up to this point we have not been keeping track of how much is going in or running off at the bottom.

lol Happy Saturday indeed!
 
  • Like
Reactions: gg2
Cx2H

Cx2H

Well-Known Member
Mass Medicinals said:
Oh wait. No way!!!!!

We just figured out what 20% run-off means. Up to this point we have not been keeping track of how much is going in or running off at the bottom.

lol Happy Saturday indeed!
Click to expand...
Greetings, no run off = salt build up, dry spots etc.

Over water = root rot, death

Happy middle ground.

Back lights up to twenty - twenty four inches.
 
Mass Medicinals

Mass Medicinals

Well-Known Member
We're working on re-designing the box. the lid will become the top and somehow we'll find a way to prop it up so a fan can circulate air.

So is happy ground 20% run-off?
 
Angus Hung

Angus Hung

Well-Known Member
for little sprouts like that i usually water only a few ounces every day or other. in my mind there roots arnt developed and they arnt really drinking yet.
 
Angus Hung

Angus Hung

Well-Known Member
theres no need for run off in my veiw.. once they start feeding then the 10 or 20% run off come into play
 
cannn

cannn

Well-Known Member
Angus Hung said:
theres no need for run off in my veiw.. once they start feeding then the 10 or 20% run off come into play
Click to expand...
Allowing for a little run off lets the soil get more properly soaked preventing those dry spots left in the pot. I also make sure to moisten soil and mix it up before potting into it because if its too dry parts of it wont absorb any water and again youll have dry spots in the soil
 
Cx2H

Cx2H

Well-Known Member
Angus Hung said:
for little sprouts like that i usually water only a few ounces every day or other. in my mind there roots arnt developed and they arnt really drinking yet.
Click to expand...
Should make some clones in a hydro cloner and see how fast (roots)they drop. I water normal, but may not water again for 7-14 days.
 
legalcanada

legalcanada

Well-Known Member
watering on a schedule at this point seems unnecessary. lift the cups and water when they are light. the roots are not fully developed either so you can also uproot them if you are watering heavily and stunt growth. you could try bottom feeding by putting water in their collection tray for them to wick up. another mistake people make is assuming LEDs can't burn because they run fairly cool. LEDs are powerful and can definitely burn, my LED is recommended 54-78 inches by manufacturer. seedlings don't need much light at all. I'd back the light up to 24 inches at least and you can always lower it if they start stretching. if you don't have room to raise the light any more you could put something translucent between the light and plants like poly
 
Last edited:
You must log in or register to reply here.
Top