Why are my seedlings so tall?

This happens to me frequently, my seedlings seem to grow vertically more than pushing out leaves and bushing out. I'm using (4) 4' foot t-8 bulbs for light, temps are steady 70-75 and humidity in the dome is 60-70. Seedlings are in plastic beer cups in coco, five days old, PH correct tap water, no nutrients yet. Light is as close as I can get with the dome on the tray.

What do you think? More light?

Ryry94 said:

This happens to me frequently, my seedlings seem to grow vertically more than pushing out leaves and bushing out. I'm using (4) 4' foot t-8 bulbs for light, temps are steady 70-75 and humidity in the dome is 60-70. Seedlings are in plastic beer cups in coco, five days old, PH correct tap water, no nutrients yet. Light is as close as I can get with the dome on the tray.

What do you think? More light?

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Take the dome off , you don’t need it at this point and move your light closer.

They are stretching for light.

they're not getting enough usable light

Drop the dome. You don't need them for seedlings. Its actually more likely to cause damping off than to help.

As everybody else said, nowhere near enough light

How to fix this or rather prevent doing it again.
Use 23W spiral CFL bulbs about an inch or so away from the seedlings with a tiny 4-inch fan blowing in the general direction to make them strong.


Fill those cups to the top with medium so roots can grow out of the stems.
Don;t keep them in there long. dixie cups fuck up roots.

Thanks very much everyone!

Kcbscrogger said:

Take the dome off , you don’t need it at this point and move your light closer.

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I wouldn't even use the dome in the first place unless there's a very low humidity. I'd also swap out at least two of the red leaning tubes in the fixture if not all of them (also spread them out out when you do use them). Red light in the early stages of a seedlings life can cause the stretch and even increase your ratio of males.

Definitely get the light closer like Kc said. When I start seedlings it's usually under the same type of t5 fixture but so close I have to raise it up just to be able to reach in between the pots and the light.

ANC said:

How to fix this or rather prevent doing it again.
Use 23W spiral CFL bulbs about an inch or so away from the seedlings with a tiny 4-inch fan blowing in the general direction to make them strong.


Fill those cups to the top with medium so roots can grow out of the stems.
Don;t keep them in there long. dixie cups fuck up roots.

Click to expand...

Ive harvest half an O out of a Dixie

So, you took 3 or four months to grow 15g of weed. hardly seems worth the effort.