Purple leaves on seedlings

urgod

Well-Known Member
I checked my 1 week old seedlings today and a couple of them have a purple hue on the underside of their leaves. I think its because its been cold (64-73 degrees), but i am not 100% sure whether it was caused by colder temperature or genetics. They are currently under a 600w MH and recieves 24 hours of light. pH 5.5-5.6 ppm= 50 @442. Growing in aeroponics/rockwool/hydroton. please let me know what you think, they are not stunted or anything, its just weird to see purple leaves, and i am wondering what could have caused it. should i raise the temperature in my grow room?


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urgod

Well-Known Member
cool, thought the 600w would heat up the place, but i guess a heater is still needed in the winter.
 

Krondizzel

New Member
I checked my 1 week old seedlings today and a couple of them have a purple hue on the underside of their leaves. I think its because its been cold (64-73 degrees), but i am not 100% sure whether it was caused by colder temperature or genetics. They are currently under a 600w MH and recieves 24 hours of light. pH 5.5-5.6 ppm= 50 @442. Growing in aeroponics/rockwool/hydroton. please let me know what you think, they are not stunted or anything, its just weird to see purple leaves, and i am wondering what could have caused it. should i raise the temperature in my grow room?


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I wouldn't worry about it, it sounds like cold temps. What is your night time and day time temps? I like to have mine at 75-80 during the day (depending on the strain) and 60-65 at night. If you are lacking heat, increase your wattage. That's my favorite method :) I am usually forced to pump outside winter air into my grow areas to compensate for the heat. Wattage means heat, no doubt about that.

Also, your PH doesn't really have to be at a fixed number. As your plant eats food and drinks water, the PH will fluctuate. It doesn't hurt it to wander in the 5.5-6.1 range because the Cal/Mag uptake is okay at 5.8, but anything below 5.8, the magnesium isn't absorbed very well. Above 5.8, the calcium has a hard time absorbing. So, letting it wander a bit is okay. Refer to chart:

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urgod

Well-Known Member
I am venting my exhaust outside, its sucking out too much air to create any heat in the grow room. I turned the heater on and set the temperature at 72 and dialed down my exhaust fan to a lower setting. I should probably get a controller for the fan that way it can control the temperature better. I dont have a night time for my seedlings, at least not yet, i just plugged the light in 24/7. So far the only strains that have a little bit of purpling are the blueberry gum, and bubblelicious. my OGs and moby dicks seems green and happy. temperature fluctuates between 64-73.
 

Krondizzel

New Member
I am venting my exhaust outside, its sucking out too much air to create any heat in the grow room. I turned the heater on and set the temperature at 72 and dialed down my exhaust fan to a lower setting. I should probably get a controller for the fan that way it can control the temperature better. I dont have a night time for my seedlings, at least not yet, i just plugged the light in 24/7. So far the only strains that have a little bit of purpling are the blueberry gum, and bubblelicious. my OGs and moby dicks seems green and happy. temperature fluctuates between 64-73.
Hey just so you know, don't plug that fan into a power strip and then into the fan speed controller. It will toast your controller. If you get a controller, make sure you only plug in the fan, directly to it, no power strips. Just a heads up bro.
 

urgod

Well-Known Member
okay, thank you again for the great advice my friend. I have another question for ya, i got a can max air duct fan. it has 3 preset power settings, so when i do get a controller, does it matter what speed setting should i set my fan to run?
 

Krondizzel

New Member
okay, thank you again for the great advice my friend. I have another question for ya, i got a can max air duct fan. it has 3 preset power settings, so when i do get a controller, does it matter what speed setting should i set my fan to run?
Why do you need a fan speed controller if you have speed control settings on the fan?

I know, dickish thing to ask lol, but, I dunno man, I suppose I would put it on max and turn it down from the controller? My best guess.
 

urgod

Well-Known Member
I think the fan controller on my fan is completely different than the "controller" i intend to purchase. U know those apolo controllers that controls temperature and humidity inside a grow room, it keeps a grow room at a constant environmental setting. also it allows for intervals of on and off for CO2.
 

Krondizzel

New Member
I think the fan controller on my fan is completely different than the "controller" i intend to purchase. U know those apolo controllers that controls temperature and humidity inside a grow room, it keeps a grow room at a constant environmental setting. also it allows for intervals of on and off for CO2.
Well, there's all kinds of "controllers". I'm referring to your basic fan speed controller.
 

minnesmoker

Well-Known Member
I'm guessing either temp or time controller, if that's the case, you want to circulate the air out, but not too fast, or all the time -- especially if you add CO2. Make sure that the setting can keep the heat at a consistent temp. around 72 - 75.

So, the above is already covered... The rest of the post was:

Some blueberries do turn purple, but that'll be more the stems and then the leaves in your buds... It'll be a tricky one at the end -- don't starve your plant for potassium, thinking it's just genetics -- if you start getting burn spots in your leaves, and curling/crisp ends you're low on potassium. That's ahead though, during flowering.
 

urgod

Well-Known Member
@ Krondizzle- thank you for the examples and expertise that you have given me, ill certainly look into some of them. That powerbox is just an overkill for me hehehe, now i know how much you are growing :P

@minnesmoker- thank you for your tips! yeah my temperature has been consistent now, i turned off my space heater because i didnt want to start a fire while i was sleeping, but now i just opened the central air vent to the grow room. Hopefully the exhaust wont suck all my heat out of my house, i will definitely see that on my next electric bill lol. i had blueberries that turn purple in the end of flowering when i flushed the first time. Is it true that cold temperature locks out potassium? or does it change the sugars in the leaf?
 

Krondizzel

New Member
@ Krondizzle- thank you for the examples and expertise that you have given me, ill certainly look into some of them. That powerbox is just an overkill for me hehehe, now i know how much you are growing :P
No, I just showed you examples of sweet equipment ;)
 
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