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The trio made their way into the tent yesterday and we now sit on the eve of week 2
From seed pop.
Light is at 20% 27” mid week I will bump it up to 25% and increase by 5-10% each week till we are at 90%
Ive been focusing a lot of Vapor Pressure Density, Vapor Pressure Deficit measures the amount of drying power the air has upon the plant. Basically, it’s how much moisture is being sucked out of the plant by the atmosphere.
You probably already know the plant uses transpiration to grow. Literally, the plant will die if it can’t release moisture through its stomata. The process of transpiration in plants is similar to how we sweat; they have stomata which are similar to our pores. But the big difference is, they do this so they can pull in more liquids through their roots to fuel photosynthesis.
When Vapor Pressure Deficit is too high, the plants might not be able to keep up with the environmental demand upon them. The air is drying them out too fast! And this will cause them to exhibit symptoms that look just like nutrient deficiencies, and the plant will grow poorly.
On the other end of the spectrum, if Vapor Pressure Deficit is too low the plants can’t transpire. Moisture may build up on the leaves, and the plant will grow much more slowly. If this goes unchecked for too long, the plants might get attacked by molds and fungi, like powdery mildew.
Reading up on VPD you’ll see all sorts of measurements of Vapor Pressure. There’s Saturated Vapor Pressure (SVP), Atmospheric Vapor Pressure Deficit (AVPD), Leaf Vapor Pressure Deficit (LVPD), plus several others not worth mentioning.
Vapor Pressure Deficit is the difference between the Saturated Vapor Pressure (SVP) and Relative Humidity. Saturated Vapor Pressure is the maximum amount of moisture the atmosphere can hold according to it’s temperature. And Relative Humidity is the amount of moisture currently suspended in the air. So to calculate the room’s Vapor Pressure Deficit all you need is two measurements, temperature and relative humidity!
But this isn’t the whole story. The plant’s experience is slightly different because they are usually a bit cooler than the room. If the plant temperature is exactly the same as the room temperature, then the plant and room Vapor Pressure Deficit levels are equivalent. But this is rarely the case! Usually, the leaves are between 3° and 5° F cooler than the room because they are transpiring. The evaporation on the leaf’s surface literally draws heat from the leaf, thereby cooling it.
We call this Leaf Vapor Pressure Deficit (LVPD), and we need only one more measurement to figure it out, and that’s the leaf temperature of the plants. To get this measurement we use an infrared thermometer (IR thermometer), and they are rather inexpensive, there are dozens available on Amazon for under $30. It’s so easy to take the temperature of anything with an infrared thermometer, like ballasts and reflectors. So if you’re like us, you’ll start pointing it at everything in sight.
So while the room’s Vapor Pressure Deficit is important, we really want to focus on what’s going on within the plant. That means we want to know the Leaf Vapor Pressure Deficit because we’re trying to grow the best and biggest harvest possible, right? Right!
Rolling into week 3 from seed roots are starting to drop through the net cups and down into the solution. Growth appears to be a lime green color, which would indicate that they are in need of more Nitrogen (N). One is struggling to keep up with the others and is looking a bit mutated and is not responding well to the nutrients I am using. I am going to add some 5.8 pH water to her rez and see if the dilution helps. Over all happy with the progress so far, Will post again next week with new progress.
What am explosive week!! Trio is looking great!! Increased ppms on two and lowered by 2% on the last girl as she is very sensitive. All three have had incredible root growth, ill take pictures next week. I added cal-Mag to their line up and increased the light intensity to 50% will stay here for the week and increase 5% each week. The pH has not been fluctuating like the last run, these girls like to stay around 5.8-6.5. The tent VPD (Vapor Pressure Deficit) has been holding stable in the green for the last 4 weeks, I am going to shift the environment over the next two weeks to the next stage of growth which is the late veg/ early flower.
So much has happened. Friday 3/12/21 upon morning tent checks, I found my trio to be very lime Green almost yellow in color starting from the bottom and affecting new growth. With the TPS-one nutritional line I was constantly chasing the pH and it just didn’t seem to have N-P-K they needed even when increasing the TDS. So I picked up a new line and they are loving it!! Sensi Grow A/B pH perfect. This line is a set it forget line. Meaning I add the recommended amounts and it feeds and stabilizes my DWC for 1 week.
So the trio reached a great point for me to try out the talked about LST 90* bender clips. They worked pretty easy and I didn’t have the feeling that I was about to snap the branches. Let see how they hold up, I would imagine I have to keep moving them so they don’t grow in. Next week should be exciting with so much more new growth. See you all then
So technically we are at week 8 but!! I messed up and added an extra germination week.
Trio are looking great! One has been flowering for the last two weeks, the other two have just started their preflower so so I switched the Nutrients up to Sensi Bloom A&B also added big bud and fish shit to their flowering feed water. Ive been heavy on the defoliation on the larger two, to increase light penetration to the LST bud sites. As youll see in the video , ive been experimenting with the 90° LST clips and found they work amazingly!! However, the ends do snap as your plants grow, so they as seeming like a one time use for this brand at least.