Heat Question

[Night Prowler]

This is the first time i used MH lights to veg. Im starting a new strain from seed and needed MH to veg for a longer period than i usally have when vegging clones on Fluros. The room itself is climate controlled less than 55% humidity (ill go just below 40% when i flower). Im veggin under 3 x 400 watt MH's and have the lights 24 inches from plant tops. The temp in the room itself is 78* farenheit away from the lights, but at ground level under the lamps im reading almost 90*. So my question is about the heat, Will the heat damage growth taken all this into consideration? Ill try to get a pic up before i log out.

 

[Night Prowler]

I moved lights up to 30" and it is still 90*F in trays directly under the lights.

 

[smokemagnet]

do you have the ballast in the room with your plants because I remember when I first started out I had my ballast in my grow room and when I set it out side of the room taking out one ballast dropped the tempature about 10 degreesif thats not the the problem then your room must not be vented well

 

[greenmonkey]

plants will grow in 90 degree temps but it will be much slower than say at 80. try putting a fan blowing directly over your plants or you could build a cool tube, that would leave no worry with heat

 

[Akornpatch]

This is the first time i used MH lights to veg. Im starting a new strain from seed and needed MH to veg for a longer period than i usally have when vegging clones on Fluros. The room itself is climate controlled less than 55% humidity (ill go just below 40% when i flower). Im veggin under 3 x 400 watt MH's and have the lights 24 inches from plant tops. The temp in the room itself is 78* farenheit away from the lights, but at ground level under the lamps im reading almost 90*. So my question is about the heat, Will the heat damage growth taken all this into consideration? Ill try to get a pic up before i log out.

Room temp at 78F is perfectly fine. I think the radiated heat at ground level will even out after some foliage is grown out. What's the actual temps of the soil? I wouldn't worry about it at this point I don't think.

 

[upnsmoke]

What Acorn said, but when you flower you need to get the temp down.

 

[Racefan]

78df is a perfect temp for flowering at cola level but 90 at root level is not a good thing at all. Is your intake low on the ground? It sounds like all of your air movement is in the upper areas of your grow box. You might try placing a fan blowing down at your floor to help disapate that hot air at the bottom of your grow room.

 

[Night Prowler]

Thanks guys. Ive used parts of everyones advise. I put all my ballast in a closet seperate from the grow area. lowered the intake and added an extra box fan. Ill look at the temp in about an hour to see what our results are.

 

[Racefan]

Well? lol

 

[Night Prowler]

Sorry its taken me long to reply to this. Investigating the ground temp I found bugs. turns out they are fungus gnats. (more on that later)


The room temp was lowered to 75*F, ground temp is now a pleasant 83*F.

Thanks to all who responded.