Lighting schedule and ventilation requirements


I’m new to this forum and new to growing cannabis. I germinated a seed a few days ago using rockwool. The sprout is about 2" in height, but I still do not see any leaf forming. In any case, I placed the new sprout in the rocks of a 5 gallon hydroponic system that’s setup in a small closet. The pump is timed so that the rocks are moistened for about 1 hour a day.
Here are my questions:

I am currently using LED lights to provide light to the plant. What schedule and light color do I need to use as the plant goes through its full life cycle?

How important is it to provide ventilation when growing in a closet? What should the rate of air exchange be?

Any other suggestions for a healthy plant growth?

I apologize in advance if these things were discussed before. Please feel free to copy the links as a response.

Thank you for your help.

For veg you can use 3000k-4500k. For flower you’ll want 2800k-3500k. 3000k-3500k can be used for veg and flower. Are you growing autos or photos? I run my photos 18/6 in veg. If you’re running autos, you can run anything from 12/12 to 24/0. Mine are in with my photos until the photos flower, so my autos get 18/6 from seed to harvest. Got pics of your little one?

I’m growing an auto. Pic is below. Sorry, what do you mean by 12/12 to 24/0? Also, does the color of the light matter? I read somewhere red light is good for sprouts until they become bigger.

Blue light is better for Veg stage, Red light for flowering stage. Seedlings drink from the air mostly, make sure you raise humidity to 70-75%, put a clear dome or cup over your plant if you have to. Mist it 3-4x a day if you can.

I don’t think 1 hour a day is good enough. Can you change it to water 4 times a day for 15? What is your schedule? I don’t grow hydroponic so I’m not sure.

Looks like she’s still stuck in the seed.

Lights on/off.

Correction. I’m growing photos. Right, the pod is still on it.

More humidity will help her pop the shell off. Or you could try to gently pry/pop the shell off. If it stays on too long, it will kill your seedling.

Wow. It’s been on there for a few days now. I’ll see what I can do when I get home. Thank you!

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Sure, I’ll try that.

I’ll increase the humidity and see what happens.

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Some follow-up questions:

  1. When does the plant stop being a seedling?
  2. Any thoughts about ventilation. I was thinking about leaving the closet door open over night, allowing fresh air to enter the closet. Would this work?


I’m really not sure what milestone people use to differentiate between seedling and veg. Never really thought about it much.

Leaving the closet door open will definitely help with air exchange. Do you have a fan in there for circulation?

ETA: Sorry. Not sure why I didn’t see this until now.

No. If I put a fan, I’d need to keep the door open all day. So I was trying to see if leaving the door open just at night would be sufficient for providing fresh air.

You need a fan for air circulation inside your grow too, not just air exchange. Leaving them open at night should cover the exchange, but you still want the air inside your closet or tent to be circulating while it’s closed up.