Clamp-on CFL Grow Light 2700K/40W.... - Page 3 - Orchid Board

FlyingBrunswick · #21 02-19-2011, 07:08 PM

Quote:

Originally Posted by johnblagg

very true that light mostly into the red spectrum will cause leggy growth but I get pretty good result using 65 watt cfls of the 2700k type.....

But you also mention that you use a variety of other lights along with the 2700k. What are the color temperatures on those? Ray didn't say they would not bloom, just that the plants will be weaker and won't have the blooming power most windowsill or daylight spectrum growers normally recieve.

NeoNJ · #22 02-19-2011, 07:58 PM

The plants all grow on a windowsill with SOUTHEAST light exposure .....

I have one Clamp-on fixure with a 2700k 40w bulb in it.
Ray states this is more RED (for blooming) but plants require both BLUE and RED.

Can anyone recommend ONE BULB that has equal amounts of BLUE-RED since I can not add a second CFL light fixture, I will have to find a Bulb that will provide equal amounts of RED and BLUE for the plants....

If you can give me the specs for the proper bulb I will replace this 2700k bulb with it ....

FlyingBrunswick · #23 02-19-2011, 08:03 PM

Quote:

Originally Posted by NeoNJ

If you can give me the specs for the proper bulb I will replace this 2700k bulb with it ....

Ray stated this already:

"Then enter 6500. The density in the blue end is about 130 x 10E12, and the red end is about 110 x 10E12 (...)"

A 6500K (daylight) bulb is almost equal in the blue and red spectrum.

NeoNJ · #24 02-19-2011, 08:14 PM

Yes, I saw that already ....

I'm trying to find a source for the 6500k bulbs..
I only find 5000k bulbs...

So if anyone knows a source of 6500k bulbs, let me know...........

FlyingBrunswick · #25 02-19-2011, 08:23 PM

I purchase my 6500K bulbs at Target and Home Depot as they are closest to me. Walmart and Lowes also carry them. Look on the packages for the temperature, it is written on them. If you are more of an online type they are easy to find on Amazon and 1000Bulbs.com.

Some lines call these bulbs "HD", "Daylight", or "Reveal", but should have the temperature written on the packaging as well.

NeoNJ · #26 02-19-2011, 08:25 PM

I've been to 3 Home Depots and they do not carry bulbs that are 6500k .... the best I could find was a 3500k bulb.

I just ordered a 6500k/32w CFL bulb from 1000Bulbs.com.

Thannks for your help!

FlyingBrunswick · #27 02-19-2011, 08:28 PM

Sorry to hear that.... I see you're in Pine Brook - I have family a little south of you that find them in HD! Weird how regional some things can be.

Glad to help!

Ray · #28 02-20-2011, 12:36 PM

Once you get to about 5000K, the red and blue ends of the spectrum get very close to each other in intensity. However, 6400-6500 seems to give a spectrum that most-closely matches the absorption spectrum of chlorophyll, which is slightly higher in the blue end:

Couple that matching with the fact that a 6500K bulb will have more energy flux than a 5000K one, and it just seems to me to be a better overall choice.

NeoNJ · #29 02-20-2011, 08:52 PM

Ok, I just bought a 100w 6500k CFL bulb, with light output = to 1610 lumens and energy used = 26w.

I'm sure this is better.

johnblagg · #30 02-20-2011, 10:10 PM

Quote:

Originally Posted by FlyingBrunswick

But you also mention that you use a variety of other lights along with the 2700k. What are the color temperatures on those? Ray didn't say they would not bloom, just that the plants will be weaker and won't have the blooming power most windowsill or daylight spectrum growers normally recieve.

LOL the other lights I use are usually not in use untill I have a reason to use them specifically.....and in fact when I am blooming something I go all the way to 2200k much farther into the red to get the most blooms I can ...in fact my phaius sat under a 250 watt hps last winter exclusively and produced If I remember 35 blooms on one spike on its first bloom.

THe other lights I have that are not 2700k are a metal halide 100 watt and a 85 watt 5000k cfl over 10 feet away on the other side of the room not exactly close and in reflectors to aim them right down on the table they are to cover......

Then I have 1 250 watt high pressure sodium that would be 2200k and much farther into the red and it is at least 5 feet away from any thing except the phaius it is hanging over again this winter...which is in spike again with three spikes this time ....a picture of it here as well ....I dont think either of these would be considered weak and I expect the blooming power will be excellent on the phaius this year as well .....It is always better to try for a balanced mix in lighting but 2700k is not that red and if the wattage is high enough will in fact do a very very nice job....in fact I have not found anything I can not grow under a 65 watt 2700k cfls it is not the most effecient and not the most balanced but it will in fact work very well if it is a higher wattage.
Being the cheapest and easiest to find they are what I use and I find they do a great job.