Accessory MH bulb to HPS Flowering

[HighWaterMark]

Working off of an Ultimate Lighting article, I need a recommendation for a 400W MH Base Up (BU) of Universal (U) bulb.

I have 2 rows of 3 20gal plants, each flowering on a 4'x4' tray inline, each under a hooded 1000W Hortilux HPS bulb. Between these 2 rows will hang 2 400W MH bulbs equidistant from each large plant (see hyper-linked article above). The 2 additional MH bulbs will provide complimentary spectra and a bit of additional illumination designed to enhance the root structure and tighten up the internodal distance.

Please take a moment to imagine what I'm trying to accomplish. Please recommend the best 400W MH bulb to get the job done. I want to enhance the base structure of each plant, especially what's under the soil all the way through to the end of the grow.

 

[Icemud]

Re: Accessory MH bulb to HPS Flowering.

Working off of an Ultimate Lighting article, I need a recommendation for a 400W MH Base Up (BU) of Universal (U) bulb.

I have 2 rows of 3 20gal plants, each flowering on a 4'x4' tray inline, each under a hooded 1000W Hortilux HPS bulb. Between these 2 rows will hang 2 400W MH bulbs equidistant from each large plant (see hyper-linked article above). The 2 additional MH bulbs will provide complimentary spectra and a bit of additional illumination designed to enhance the root structure and tighten up the internodal distance.

Please take a moment to imagine what I'm trying to accomplish. Please recommend the best 400W MH bulb to get the job done. I want to enhance the base structure of each plant, especially what's under the soil all the way through to the end of the grow.

I love the Phillips Mastercolor Ceramic Metal Halides. They only go up to 400w, come in either horizontal or vertical mount, and have to be run on magnetic 400w ballasts. I have looked at the spectrums of many bulbs made for growing, and these are far superior at a fraction of the cost. I would highly recommend them. I run 1 400w CMH and 1 600w Ushio HPS in my flower tent and so far always manage to be very pleased with the outcome. I just flowered my Pre98 Bubbas for the last 4 weeks only under the 400w CMH and it was incredible..

 

[Icemud]

Re: Accessory MH bulb to HPS Flowering.

Here are the spectrum charts for the CMH, A HPS and a typical MH bulb. You will see that when compared to the Par Curve, the CMH has the closes resemblance, as well as it is much fuller of a spectrum where typical MH and HPS fall short of the Near IR when compared to the CMH.

Ushio Optiblue MH (notice the intense bands of light, but many "holes" in the spectrum, and also lacking intensity in the far red.

Typcial HPS vs CMH

Hps Spectoral Output (notice it is very heavy in the orange, but misses quite a bit on the far red when compared to the CMH

Par Curve

 

[HighWaterMark]

Re: Accessory MH bulb to HPS Flowering.

Icemud,

Thanks a million for the universe of information.

I fear an apparent asset may become a liability. Tell me your opinion; I value it as it's based in reality where mine is based moreso in science. The Phillips Mastercolor CMH has a healthy dose of long wavelength red-orange which will facilitate bud production and quality. Will it also negate the blue wavelength's facility at shortening inter-nodal distances?

Am I robbing Peter to pay Paul, inducing stretch?

 

[HighWaterMark]

In other words, do I want a heavy representation of reds in my MH or CMH when I'm trying too avoid stretch, decrease inter-nodal distances and develop a vital, full root structure?

 

[Icemud]

In other words, do I want a heavy representation of reds in my MH or CMH when I'm trying too avoid stretch, decrease inter-nodal distances and develop a vital, full root structure?

Great question but I am not quite sure how to answer it. The CMH bulb spectrum is heavy in red and blue, and the addition of a auxillary light source will definitely promote thicker and fuller auxilary buds. Now as far as red vs blue in the stretch, I don't think that just adding and additional MH bulb will make that much of a difference as far as stretch vs tighter internodes. I know in the presence of blue light vs red light, typically the blue will cause shorter distance but I believe the studies that I have seen were done using only blue light or red light, not full spectrum or mixed spectrum lighting. With the CMH you are getting the best of both worlds, the only bulb that is better for a full spectrum with more blue than red would be the Hortilux Eye blue bulb which is very similar to the CMH just heavier blue than red...as for much of a difference in growth and being an auxillary light source with HPS being your primary, I think that either bulb would do.

As for a more abundant root structure, I would suggest using a air pruning pot like smartpots which will build a thicker root base. Also good watering practices will increase root structure as the more you water and force feed the roots, the less the roots will need to search for water and will stay smaller, vs letting the soil dry out between feedings which will allow the roots to search more, developing a larger rootball. As far as light vs root span/size, I haven't seen any studies relating the roots to the color scheme of lighting. I wish I had more info for you, overall the CMH or the Hortilux blue are the best bulbs in my opinion in the market, either will give you much fuller and better spectrum.

 

[Icemud]

You may want to contact the member Hosebomber, he is probably the most knowledgeable on this forum when it comes to lights, spectrums and related info.

 

[HighWaterMark]

Hortilux 1000W Standard Metal Halide:

Hortilux (enhanced) 1000W Blue Metal Halide:

Keeping it simple. If you were vegging a young cannabis plant somewhere in the United States where the law limited your number of plants, where eventual yield per plant was paramount, and at this stage you wanted to develop a vital root ball and a physiologically strong stalk/stems with a mature, well-developed vascular system and tight inter-nodal spacing (BTW, I am in love with Caledonian Tree Co. Air-Pots).

Again with the veg. Which spectrum do you want?

 

[Hosebomber]

There are a number of factors that come into play when you are using light spectra to manipulate growth rates and shade avoidance. If you have a very large presence of green light combined with high levels of overall saturation or with a combination of low end reds (610-630nm) then you induce the shade avoidance receptors and the plant stretches more. Likewise, the stage of development of the plant also triggers elongation. When the plant goes into flower, those branches that are going to produce flowers stretches out so that the seeds it produces will be spread as far as possible (regardless if the seeds are pollinated or not. This type of stretching cannot be fully removed simply with light manipulation. It's not a matter as simple as how much of what spectrum of light the plant is receiving.

 

[HighWaterMark]

Hosebomber, I appreciate your time and your reply. And I do understand the point about stretch being multifactorial as are most things in the biological sciences. Allow me to clarify my question. In the early-mid stages of vegetation, am I doing my plant any favors by augmenting its illumination with low-end reds as found in the spectra of the Hortilux Blue (above)?

In deciding between the two Hortilux Metal Halides (above) my instinct is to stick with Standard Metal Halide at around 60W/ft². Do you agree or disagree?

 

[Icemud]

Hosebomber, I appreciate your time and your reply. And I do understand the point about stretch being multifactorial as are most things in the biological sciences. Allow me to clarify my question. In the early-mid stages of vegetation, am I doing my plant any favors by augmenting its illumination with low-end reds as found in the spectra of the Hortilux Blue (above)?

In deciding between the two Hortilux Metal Halides (above) my instinct is to stick with Standard Metal Halide at around 60W/ft². Do you agree or disagree?

The two best Mh bulbs are the Ceramic Metal Halide by phillips and the Hortilux blue. Going with a Standard MH will give you less light in the PAR curve because regular MH bulbs have very high peaks, but are not full spectrum. Just look at the spectoral outputs of the Hortilux blue and the CMH posted above vs a regular MH. You will notice the Hort Blue and CMH are similar to sunlight, CMH heavier red, and the Hort Blue higher blue... Both of these bulbs are excellent and you will do fine with either choice. The difference between the 2 is so minimal that you probably couldn't even notice a visual difference in the plants growth.

I disagree when sticking with the standard MH, again look at the PAR curve I posted above, the standard will not outperform either of the above mentioned because the spectoral output is not close enough to the par curve with the standard MH, whereas the other 2 are very similar.

 

[HighWaterMark]

Icemud (and Horsebomber), many thanks. I've studied those "Percent of relative energy" charts to the point of silliness. At the risk of beating a dead horse, please look at my Post #8. Would you both select the Hortilux (enhanced) 1000W Blue Metal Halide over the Hortilux 1000W Standard Metal Halide as your primary vegitation bulb (post-seedling phase) despite the bolstered low end reds (610-630nm) which induce an unquantified amount of stretch?

To put it another way, regarding the Hortilux (enhanced) 1000W Blue Metal Halide, do the PROS outweigh the CONS?

HWM

 

[Hosebomber]

I would have to go with the enhanced.

 

[HighWaterMark]

Thank you, Hosebomber.

Icemud, are you in agreement with this highly scientific study?

 

[Icemud]

I personally would go with the ceramic metal halide because the bulbs rock, but out of the 2 choices you listed above, I definitely agree with hosebomber and would rock the enhanced blue horitilux.

 

[Hosebomber]

Remember that this is going to be used in conjunction with a much higher wattage HPS bulb. I think that giving a bit more blue from the MH portion of the setup will perform better. I do agree with Icemud on the fact that if you are going the whole grow through with one buld the CMH is probably the better option. My personal addition to supplement a HPS would be a set of LED's with 420, 455, ~470 and 730 nm.

 

[HighWaterMark]

Icemud and Hosebomber, thanks for the healthy debate. As I mentioned before I'm working off of ideas in an article that strike me as scientifically sound (and I'm a scientist). I'd love to augment the HPS with LEDs, perhaps adding a touch of 680nm spectra to get a dose of Emerson Effect, an aspect of the electron transport chain that has always fascinated me with chloroplasts. My initial blueprint is a 2300 sq ft footprint divided into 6 rooms providing a perpetual harvest with maximal efficiency. It's a box within a box that just fits beautifully and is modular, so modular in fact, I'm nearly done after building 6 identical walls and 6 smaller identical walls. 100 woman/man hours at most, fashioned by the owners (a clever way to cut labor costs).