Spectrum 6400K Tube = Plant Growth Tube?

Just wear sunglasses.

Sort of. Plants will respond to any light, but will respond better to light that is more concentrated in the red and blue spectrum. Hence the purplish color of the tubes that are sold specifically for growing plants.

According to internet search "Plant growth lamp 6400K" can display quite a few relevant webpage. If typing "Plant growth lamp 2700K" for example, no relevant webpage.

Anybody knows why?

In choosing the correct plant growth lamp, light spectrum (how many K) is more important than the physical color (such as purple)?

Indeed, the blue and red spectrums cause the plant to produce the highest amounts of chlorophyll which fuels photosynthesis, which produces your leaves, flowers and fruit. Blue spectrum sources are used for green, leafy plants, and it also keeps the plants more compact. Red sources trigger hormone growth in the plants which produces flowering and fruit. Ideally, you would start your seedlings or clones with the blue spectrum until they are mature enough to start bearing fruit, then switch to red.

It would also be of benefit for you to generate CO2 for your indoor garden, and make sure you have good air circulation throughout the plants to avoid rot.

Here is an extract of the website

en.wikipedia.org/wiki/color_temperature

"..Color temperatures over 5,000K are called cool colors (blueish white)..".

Can we correlated the color temperature rather than physical color?

LED seems too dim and not as energy efficiency as a flourescent lamp.

Anybody grows indoor plant by daylight flourescent lamp?

I just have to add that the green color of plant life is the reflected color. All other parts of the spectrum are absorbed and used by the plant. Also, note that fluorescent lamps can be and are a blend of color rendering fluorescent powders that can be customized as you like. The "Grow Lights" have been blended to provide the most appropriate spectral content that fluorescent lamps can generate.

The color that fluorescent lamps have the hardest time generating is red. This is not to say that they can't do that, just that it takes more red fluorescent powder for a given brightness than it does for the other colors.

As an aside, I would agree and suggest that CFTs or FTs are very poor light sources for the serious hydroponic gardener. Getting the seedlings off is about the only use for them in the indoor garden...or for a shop light!

Ebay has a plethora of proper grow lights available in the red and blue spectrums, and a wide assortment from incandescent to led, such as this light

But I saw most aquarium shops, they use FT and the water plants grew well.

Sometimes I doubt the plant grow lamp, high percentage of their cost grows to advertisment.

Do you mean FT is not suitable for seeding only?

Here it use FT and color temperature

http://cgi.ebay.com/4Ft-4-TUBE-T5-FLUORESCENT-BULB-PLANT-GROW-LIGHT-SYSTEM-/370527789362?pt=LH_DefaultDomain_0&hash=item56452d6132#ht_3682wt_1030

They are fine for low-light, non-fruiting/flowering green, leafy plants for your aquarium/terrarium. I assumed you were trying to grow something you could consume, in which case, HID or high-flux led is the only way to go.

Sayanora.