Posts tagged metal halide

Chronicology 101: Addressing Your Lighting Needs


Red light. Green Light.

Recently, someone asked us “What is the best way to light marijuana?” We thought of 3 ways you could do this. There is the most common way which is to use a lighter, the more traditional route with matches, and the ultimate earth friendly option of using a magnifying glass. Okay, so starting the post like this seemed much funnier before we actually wrote it.

In all honesty, we were asked if marijuana does exceptionally well under certain colors of light. We were able to rule out the color green pretty easily, because plants our green. Everything we see appears to have color because that is the light which is reflected by the object. Plants, in particular marijuana plants, are green because the reflect, and therefore do not absorb green light.

All the colors of visible light have a wavelength that fall within the range of 400 and 700 nanometers (nm). Green light has an approximate wavelength of 510 nm. Very similar in wavelength to green light, is yellow light with a wavelength of 570 nm. Red light has a lower wavelength and blue light, higher.

The red a blue wavelengths are needed by plants in order to produce chlorophyll A and chlorophyll B. This is why the LED grow light set ups have red and blue LED’s. Unfortunately, these lights are not very powerful.

We recommend using an Eye Hortilux bulb in your set up. Metal halide bulbs have more blue spectrum light and are better for vegetative growth, while high pressure sodium lights produce more red spectrum light and are better for the flowering stage. Hortilux produces both, and we recommend them on the basis of their customer service, warranties on their products, and because they are proudly made in America.

If you have any further questions, or need clarification on anything we have said, please feel free to cnatact us by posting a comment to this post or emailing us at

Jah bless!!!


Lights and Light Cycles


LED Grow Light

It seems as though many of the questions our readers have been asking lately You focus around growing marijuana, so I thought it would be appropriate to clarify some things.

In the last post on cloning plants, I mentioned the words vegetative and flowering. These words refer to the two light cycles of marijuana that you must consider when growing indoors. The first cycle, vegetative growth, is when the plant is growing bigger. When it starts off as a seedling you want the plant to be in the vegetative state, “vegging”, so that it can grow up to be nice and big and bushy. During the vegetative state the plant will begin to smell like pot, however there will be no buds and you will not be able to get high off of any of the plant, yet. To keep your plant in a vegetative state is fairly easy, all you have to do is keep your light on 24 -16 hours per day. Some people believe that giving the plant some time off gives it time to rest and actually makes it grow more than having the light on 24 hours per day. Others say that the best way to achieve the highest yield in the least amount of time is to just leave the light on around the clock. That is a personal preference kind of thing that you will need to experiment with and make a decision about on your own. You need to figure out what works best for you.

So once your plant is big enough and mature enough, you can force it into the flowering stage of growth. The flowering stage mimics the natural processes of the fall, where the days get shorter and there is less light. You will know that your plant is ready because the newest sets of leaves that emerge will not be pairs, but the leaves will be staggered on either side of the stem. You can flower before this if you want, however it is not recommended. In order to force your plant into the flowering stage, you need to get it on a 12 hours of light and then 12 hours of dark cycle. Make sure that you schedule the 12 hours of light to be the time that you can take care of the plant, because you do not want to contaminate the darkness. Remember this. I’ve heard of people giving there plants a whole 24 hours of darkness before switching to a 12 on and 12 off schedule, but personally we feel its a waste of time. Again, thats one of those things you need to figure out for yourself, everyones growing conditions and plants will be different, feel it out. Once, you are in the flowering stage you can grow your plant until several things occur. Some of the leaves will begin to turn yellow and fall off, but this isn’t a tell tale sign. The best way to determine maturity is to look at the hairs on the buds or the trichomes on the buds and leaves. If you don’t have a magnifying glass or lupe, just look at the hairs. When either half of the hairs or half of the trichomes have turned orange, let your plant go another day or two for good measure and then chop it down. Make sure to hang it upside down to dry and then do with it as you please.

When considering what lights you are going to use you need to realize several things. The yield that you get is directly related to how powerful the light that you use is. You could grow marijuana with those corkscrew shaped CFL bulbs if you wanted, you should use as many as you can though, and just note that this method is not recommended. CFL’s are great for seedlings and clones, since they are not too powerful you aren’t likely to burn your plants when they are young. During this stage, we use a traditional fluorescent bulb (one of the long tubes) that is specifically designed to emit the right spectrum of light that plants need. You can find these in many stores, labeled as aquarium bulbs, greenhouse bulbs, plant friendly bulbs, either way they are not too hard to find. However, in order to grow some heady herb you need to get serious. Tommy Chong doesn’t smoke anything that was grown with a CFL or a fluorescent bulb for that matter, neither does the guy from Super High Me, or anyone who buys weed from a medical marijuana dispensary. The important thing to remember is LED, HPS and MH. Light emitting diodes, high pressure sodium and metal halide.

LED’s are the future. We’ve never used them but we here good things and they are super efficient. WE’ll try to look into that more. As far as MH and HPS go though. Metal halide is preferable for vegging and high pressure sodium is preferable for flowering. While you could use a MH for vegging and flowering and a HPS in the same way, if you are going to go with just one light we recommend you go with a HPS over a MH. The bulbs are kind of expensive and if its your first grow, start with just an HPS, and the next time around you will have everything you need so buying just one bulb won’t be too much of a burden. These lights are extremely powerful and get hot, so you will need a ventilation fan, that will ideally have an exhaust duct that leads outside or into a different room. Just as a last recommendation regarding lights, don’t buy online and pay cash. There is really no legitimate reason that anyone would believe why you had any of this equipment, your only legitimate excuse is that you have an indoor hydroponic vegetable garden. But, you have to admit that in itself sounds kind of hippie-ish and sketchy. So find a hydroponic supply store or garden center where they sell this stuff, and like I said pay cash. Its always good to leave as little of a paper trail in everything that you do in life. You don’t want a paper trail when you buy equipment to grow weed or when you walk out of the bathroom at the bar, under every circumstance I can think of a paper trail is just not something we as humans desire.

Take care, as always give us your questions if you’ve got any. And, send us your myths. If you haven’t already go to our “Contact Us” page and like us on Facebook and Twitter.


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