Welcome to Letters to Rev one and all. Today’s Go to the Light theme is as you’d suspect, about lighting for cannabis plants. I don’t consider myself a lighting guru at all, but I have had the opportunity to use a lot of different lights over the years and see how growth differs.
Growing cannabis all naturally indoors, like TLO (True Living Organics) style, your lighting matters a great deal. I prefer using the same lighting from sprouting to harvest. If that’s not possible I like to keep the spectrum (color temperature/kelvins) the same. All my LED lights are 4000 kelvins, and all my HID metal halide lamps are 6500 kelvins.
Alright then earthlings, let’s rock and/or roll with today’s “Letters” to Rev…
Go to the Light, Question #1: Dimming and Automation?
FROM: Marius O.
“While reading your advice from letters to Rev in Skunk Magazine, I came across the tip about dimming lights to finish flowering better. I am deciding whether or not to get the NextLight control panel to be able to do the sunrise/sunset dimming. Do you believe this is valuable? Also, how do I make the best use of this control panel? I am running two NextLight LEDs.
I love TLO 2nd Edition. How’s the latest edition going? Thanks.
Rev’s Answer to Q1
Howdy amigo. Yeah, a great question there homeslice. First, let me say that I am still messing with the whole dimming thing big. I have only been doing it for a few runs now, but in that time, I have observed some cool things. I also have only recently learned about that lighting control panel from my buddy Jarrod, over at NextLight. It sounds awesome, and the price seems decent as well.
I actually began dimming my lights at the end of the plants’ day due to high temperatures. So, the next morning when the lights came on, they would still be dimmed until I raised the power levels. This is an awesome countermeasure to high temps. I also noticed a really nice benefit from this move as well regarding terpene expression. My plants (genetics I am highly familiar with) were extra stinky and tasty, by a definitely noticeable amount. The overall elegance/smoothness of the smoke was also kicked up a notch.
The automated control panel will start your plants out dimmed and end them dimmed just like Mother Nature does in the outdoors. I always tend to trust Mother Nature, so this is a no-brainer for me. The panel will also dim the lights if temperatures get too high, a super cool automation indeed. Let me show you how I do the whole (non-automated) dimming thing these days.
Rev’s Dimming Schedule Details
- My plants flower on a photoperiod of 12/12 (12 hrs. ON/12 hrs. OFF) unless they are landrace sativas.
- I dim my lights to about 50% power approximately 30 minutes before lights out. When lights come on in the morning, I allow them to remain at 50% for the first 30 minutes.
- I also use the dimming feature if the ambient temperatures get too high. I also use the 50% power setting for this purpose.
The automated unit from NextLight you are talking about seems like it rocks huge to me. That being said, I am always near my gardens and I monitor them remotely on my iPad. I don’t really need that automation, but, if my gardens were “on their own,” like if I worked 9 to 5 or whatever, I would absolutely get a couple of those control units.
Go to the Light, Question #2: Eye Hortilux Blue MH?
FROM: P. J. S.
“Hi Rev! Big fan here, and in fact, many people in my town use your TLO methods. We have a lot of good pot here. I sort of followed my friend, who follows your advice very closely, when it came to setting up my growing room. His plants were incredible, while mine were just pretty good. The only difference that stands out is the fact that he uses your recommended Blue Hortilux HID lighting. I use super HPS full spectrum lighting. Before I make the fairly spendy purchase of these Hortilux Blue bulbs I just wanted to ask you, does the Blue Hortilux make that much of a difference?
Thanks, Rev, can’t wait for the new book.”
Rev’s Answer to Q2
Yes! The Eye Blue Hortilux makes that much of a difference, in my opinion/experience. The spectrum of this bulb borders on magical if you ask me. I still use these bulbs during the winter in my gardens. Not only because they work fantastic, but they are heaters and lights for me in the winter, saving on my heating bill.
I have tried a lot of lights, not all of them nearly, but enough to feel strongly that the Blue Hortilux is far superior to any other HID lights for sure. In the summer months I run 420h LED lights from NextLight and I also dearly love those lights.
The Blue Hortilux runs 6,500 kelvins as far as color temperature, which is very “blue” indeed. Plants tend to use more nitrogen under the blue bulbs, and most peeps kind of get tweaked about flowering with a blue light like this one. The common wisdom is vegetative growth with MH, and flowering growth with HPS. They have heard it and seen it so many times it seems like an accepted rule. It is not, and all you have to do is flower with one of these Hortilux Blue lights to see what I mean.
Here’s a link to where I get my Hortilux Blue bulbs: Hortilux Blue (Daylight) Super Metal Halide (MH) Lamp, 400W. Another article you may want to have a look at as well: Cannabis Grow Lights: Flowering with Blues. I use my MH bulbs for three flowering runs before replacing them, and I could easily go four if needed.
Go to the Light, Question #3: Sprouting Lights?
FROM: Lynn L.
“Do you sprout and flower under the same lights? I have two rooms I can set up and one I am using to flower in and the other for vegging and sprouting and cloning. I have some amperage concerns. I read how you sex your plants easier by sprouting them under a 12/12 photoperiod. How do you pull this off if you have plants in veg and in flowering? Do you have another area to sprout in, and what lighting do you use there if you do?”
Rev’s Answer to Q3
Hey Lynn. Well, in the winter months when I run 400-watt metal halides to flower with I use a 250-watt metal halide to sprout with. Both are Hortilux Blue bulbs. In the summer months, I flower with LED lights (420h) and I sprout with HLG 300-watt LED lights. Both of these lights run 4,000 kelvins for color temperature. I am a big believer in keeping the lighting very close regarding color temperature throughout the plants’ lives.
I do use a tent in my vegging area to sprout in. This tent does double duty for sprouting and for a pre-flowering warm-up, so to speak. I run most of my vegging plants under T5 lighting, which works very well, but about 10 days before I am going to flower any plants, I toss them into this tent under the more intense lighting. This really ups my yields. Alternately I often just put them in flowering tents early under a 16/8 photoperiod for 10 days before changing them to my flowering photoperiod (12/12).
When sprouting under the 12/12 photoperiod you need it to be pretty dark when the lights are out. You don’t need it to be dark like flowering time dark, but so dark that you would be blinded yourself works fine. After 10 days above ground move the sprouts to a vegging photoperiod like 18/6, and you can easily sex them when they are 30 days of age. If I remove a plant during flowering—which happens sometimes—I often use that empty space to sprout in the flowering tent along with the other flowering plants.
I hope you all enjoyed this Go to the Light Letters to Rev article today. Lighting is super-duper important—duh! You can change your whole grow around by using proper lighting. Of course, you also need good genetics, buzz by Kingdom Organic Seeds, and have a look at some lovely options. Don’t forget to grab a copy of my 2nd Edition TLO book and get your supernatural on when it comes to growing top-shelf cannabis.
Oh, and hey, Marius from question 1… I am almost done with the new TLO book. I have a couple of chapters left and some addendums and that’s it! Should be done in the summer. Hope so, whew! It’s really good, and I’m not just saying that because I wrote it LoL 😆
I’m outty for now, see y’all back here next Tuesday for the next installment from yours truly. L8r G8rs…
- REv 😊
I'm The Rev, and I have been with SKUNK for about a decade now. I hail from Southern California, spent mucho time in Northern California, and now reside in Southern Oregon; always coastal. I am an all natural style cannabis grower and I have written a couple books on the subject - check out True Living Organics 2nd Edition on Amazon - I have been growing for over 45 years, and I have been breeding cannabis for over 30 years. Check out kingdomorganicseeds.com to see some exotic selections. Growing connoisseur cannabis is what I teach mostly, growing it in living soil without using liquid organic nutrients to feed the plant. I am also a highly skilled synthetics grower, hydroponics, aeroponics, DWC/SWC/NFT, Ebb and Flow, and soilless, but I cringe when smoking synthetic grown herbs, so for the last 15 years or so I preach the artisan style of all natural growing, specializing in container growing. Cheers and welcome aboard.