Autoflower and lights

[ahbenshaut]

I just got some Northern Lights Autoflowering sprouts. Can I start them under a 400 Watt light or is that too much to start with?

thanks for the help

 

[OEF Vet 11B]

I have mine under a 400w mh they're fine. Just don't put them too close

 

[Justalittle]

I have mine under a 400w mh they're fine. Just don't put them too close

So just wondering here. When you use a 400 watt light for a seedling, since you can't keep it close, does it make them stretch?

 

[ahbenshaut]

cool thanks

 

[OEF Vet 11B]

I don't really know I guess. I grew under a t5 really close and they look the same as my plants under an mh from 2 ft away. With an air cooled tube it's easy to keep the Temps downs. I'm still learning and experimenting with light distances. I'm sure someone will chime in with a more precise answer but I can try to answer any questions you have. I have about a year under my belt.

 

[ahbenshaut]

oh yea...good point. And is 78 degrees too hot?

So just wondering here. When you use a 400 watt light for a seedling, since you can't keep it close, does it make them stretch?

 

[OEF Vet 11B]

I think it's hitter than preferred but if your plants aren't showing signs of heat stress they may be okay for now.

 

[Justalittle]

oh yea...good point. And is 78 degrees too hot?

Temps are a little high for my liking but if that's all you can do then don't worry. I like my seedlings at around 74.
Do you have a fan moving air?

 

[ahbenshaut]

Temps are a little high for my liking but if that's all you can do then don't worry. I like my seedlings at around 74.
Do you have a fan moving air?

Yep. one of those little clip-on fans.

 

[OEF Vet 11B]

And a good exhaust?

 

[ahbenshaut]

And a good exhaust?

No exhaust yet. I have the fan, i just have to drill a hole in my wall

 

[OEF Vet 11B]

Exhaust would help Temps go down greatly. I'd make that a priority

 

[Qapla]

So just wondering here. When you use a 400 watt light for a seedling, since you can't keep it close, does it make them stretch?

The distance of the light from the seedling has more to do with intensity than heat. Seedlings can't take nearly as much PAR as a vegging or flowering plant. So no, it won't make them stretch unless you have the light too far away.

 

[Justalittle]

The distance of the light from the seedling has more to do with intensity than heat. Seedlings can't take nearly as much PAR as a vegging or flowering plant. So no, it won't make them stretch unless you have the light too far away.

Thanks but I think you missed my point?

 

[Qapla]

Thanks but I think you missed my point?

Its possible, thought I got it. You asked if the seedlings will stretch due to light distance required, presumably due to heat. I was saying that with high power lighting, light intensity/PAR is probably more of a concern than heat from the light. As long as the area is ventilated. At the distance required not to burn the plants from heat, there's likely still too much PAR for seedlings so you have to raise it up even higher. So no, it won't make them stretch unless the light is really far away. Unless I'm still missing something?