View Full Version : using CFLs, why use 6500k (day) bulbs for veg, then switch to 2700k for flowering?
remix8604
06-30-2011, 04:48 AM
i heard this around the net but not really sure why or that i should even do it. will the 6500k cfls do the trick for flowering?
Purple Daddy
06-30-2011, 01:35 PM
Depends on how many plants you have, I don't think 6500 is going to be enough for just one plant to finish. I don't know why you would want to give them less light for flowering? It's the hours of light/darkness that trigger flowering not the intensity of the sun although the natural sunight is less intense near the end of budding.
CanGroIt
06-30-2011, 02:01 PM
i heard this around the net but not really sure why or that i should even do it. will the 6500k cfls do the trick for flowering?
6500k and 2700k is the Kelvin rating. They are heated to different temperatures, once plugged in, and emit a certain spectrum of light per rating or temperature heated to. The 6500k has worked better for veg than the 2700k, so says a lot of people on the net, and vice versa for flower. IMO you can use either or, doesn't really matter....but that's just my opinion and I only use CFL's for veg and HID for flower....so I can't really speak from experience, I've never flowered with CFL's before, good luck....
Happy Growing....
CGI::::::
RackitMan
06-30-2011, 04:21 PM
Check out my bubble bucket thread in basic growing. It vegged beautifully on a single 23w 2700K CFL.
remix8604
06-30-2011, 06:15 PM
It will be my first grow. So I'd be happy if I got 2 female pants to finish. I'm pulling all my suplies together now. Already made my first mistake by buying 2, 15 watt cfls (6500k). I'm going back and getting like 2 50 watt cfls. I was going to get the soft white 2700k cfls for flowering. Now maybe I'll save for a good light to flower with.
What would be a good light with low watts for 2-3 plants. Energy bill is alittle issue.
Douglas1
06-30-2011, 08:08 PM
not a terrible mistake to make.. just use the 15's somewhere in your house instead of an incandescant.. save some money
remix8604
06-30-2011, 11:04 PM
Recomend a light for 2-3 plants? Would a 100w HPS work?
RackitMan
07-02-2011, 03:49 PM
The problem with small HPS is usually they are paired with a very cheap and inefficient ballast. A number of years ago an engineer tested a popular 150w HPS lamp. The ballast itself was pulling over 100 watts.
If you cannot go 400w or larger, I would go T5 or LED. 250w HPS is marginal.
remix8604
07-04-2011, 01:26 AM
ok so what i found and wonder if this will work and how many plants could it grow. would 2 - CFL, 42 watts, 2035 lumens 6500k work?
also i noticed alot of CFL bulbs say 15 watt equivalent to 60 watt bulb. i need the actual bulb watts, not what it replaces, right?? the highest watts i could find was a 150 watt cfl. it looked like an energy bulb on steroids. then again.. im not sure if it was equivalent to 150 watts or was 150.
CrackLemonade
07-07-2011, 09:43 PM
A number of years ago an engineer tested a popular 150w HPS lamp. The ballast itself was pulling over 100 watts.
If it pulled a hundred watts how many watts got to the bulb?
Purple Daddy
07-08-2011, 12:30 AM
also i noticed alot of CFL bulbs say 15 watt equivalent to 60 watt bulb. i need the actual bulb watts, not what it replaces, right?? the highest watts i could find was a 150 watt cfl. it looked like an energy bulb on steroids. then again.. im not sure if it was equivalent to 150 watts or was 150. >>>>>>>>
The 150W CFL is a 42 watt bulb, the watts are the power consumption you need to look at total lumens. A typical 40W flourescent shop light produces 2800-3200 lumens. They comparison is with an incandescent bulb which produces far less lumens per watt then a CFL or HPS/MH set up. LED's use even less power consumption while producing more light/lumens per watt then either incandescent or CFL's.
jon420
07-22-2011, 02:14 PM
CFL's are great but you will find that using a mixed spectrum 6500k and 2700k during flower will significantly increase your resin production. Using the 2700k during veg will influence stretching but nothing major. I find that the 6500k alone during veg produces the strongest growth when using CFL's only. Check out my first log, all CFL and if you have questions feel free to ask.
BuddyBea
07-22-2011, 05:20 PM
Newbie here.
Just my input, from a biological standpoint. (Which I'm not a newbie at. :)) 5000-6500K during vegatation and then ~2700k during flower makes much sense. Lets also remember the long light cycle during veg and ~ 12/12 during flower...
This type of plant grows during the first few months of the year and then flowers (naturally) in the fall. Naturally the sun is more intense in the spring and summer and also during that time gradually stays "up" longer. (Think 6500K and long light cycle.) Then, twoards Sept/Oct, as the earths axis tilts, the angle of the sun as it relates to hitting the earth changes, and is less intense. That's when it gets darker earlier (think 2700k and 12/12) and the plant would naturally bloom.
To me it all seems realitive.
On the other hand, are plants and animals (and bacteria, viruses, etc.) very adaptable. Yes!!!!!
Powered by vBulletin® Version 4.2.5 Copyright © 2025 vBulletin Solutions Inc. All rights reserved.