If you can control your environment down to holding an ambient to 3 deg. F rise with lights on. Limit night drops by 10 and hold +/- 5% RH with an average set of 45%. You can produce with
consistency. Being able to run consistently is a key factor in reaching for potentials. The location of the thermostat is important to the control of the "layers" of temp in the room. When you look at a thermometer. Your only reading the ambient temp at that level. Put your hand under your (HID) light at the canopy level. That's not the room's ambient temp at the therm level, is it?
I've found if you can keep your canopy at the mid to higher 80's (all about adjusting light hood distance). The middle area of the the plant to about 73-75 and the root zone around 68. Your golden for a soil grow operation.
For hydro, you need to keep the res/pot temps below 69 to ward off root rot...... Placement of your temp controlling devise is key in this limit factor.
After that is proper nutrient ratio's and supplementing for potential. I do it simply. I also make my own supplements and in synthetic use, stick to 2 parts of a 3 part system. I don't need the veg. nutrient as I up pot with 30 day soil and Solo's last just right to up to 1, to 3's and or 5's and 7's being last pot for bloom. I use a mix of re-amended used soil at about that 30 available nutrient days. I feed daily from day 1 (I have the 30 day soil balancing the increased needs of the "stretching" plant. As the soil nutrient tapers, the "stretch" is ending) off the bloom room and amend the same. I water a metered amount that does change as the plant grows. That metered amount last me from lights on to the next day, lights on. This brings more O2 to the roots and that is a good thing.
The supplements end at the last 2 -3 weeks of the plants life. I run longer then most people I have ever met and I do that for final quality.. Very important.
If your growing from seed, or even clone. You move the plant out of it's familiar environment. It will react by "
shifting" it's growth patterns to that new environment. Thing is, it could take a whole single generation and the next clone express's that
shift, or it could take 3 or even more generations (the seed plant is run from seed once and the following clones show the shift). This is a physical change, potency's and content, do not "shift" so much as you enhance or harm them by what you feed and when.
Changing or affecting trep profiles by what you feed or by what you supplement is quite true. Manipulating and doing it to get consistent results. Locks you into 2 forms of S that with the other part of the compound, effect flavor enhancement.
Mag Sulfate will make a more berry profile stand out. It also increases trichome production. So from that fact alone, your increasing Cannabinoid and terpene levels by volume.
Potassium Sulfate will make a more citrus profile stand out. It also does the same as The Mg for trich's/terp's. It also helps increase yield by adding mass to buds. It will also help strains that can color, to color.....
If you doubt this information. Simply try it.
I make my own of each and use each in an equal amount by volume. Longer running of chemdog makes the second harvest smell very blue berry/grape like. I have patients that go bonkers for that specific "late harvest" dog...The first harvest is the more conventional lemony profile. I have an old,old pheno of Blue Berry, that basically smells little like BB but, has a light spicy/earthy twang. Longer running makes her more traditional but, it never did have much BB profile to it. Slaps you hard. Right into a chair and you sit there, quite stupid for about the duration.....
I find by balancing the 2 by volume. The plants will retain their normal profiles and enhance them too. A few strains will shift one way or the other a bit, and some change profile with extended run times....
Adjusting them by any amount would be only limited by the way you meter them....
Another thing is you can increase THC and/or CBD by pretty precise formulation of a mix of micro nutrients. Key being Fe and Mn. You also add others to balance/buffer and enhance the reactions of the used micro's relationships with each other.
Mel Frank did work in this, and gives a formula to do just what I'm talking about here. Thing is, back when he was doing this work. He didn't know the formula he listed, does more to raise CBD then THC....A very simple adjustment of that formula would flip that to more THC. You need to make this stuff by weighing dry chem's and mixing with a single gallon of water... Read his books, tells you how.....
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