Smart Cabinet - arduino constant VPD

Currently vegging at a targeted 1.0 kPa VPD. Feels like about 25c in the box. Exhaust power, humidifier, dehumidifier, heater and lights are all connected to an Arduino running a home-brewed automation script. Exhaust power is adjusted every 3 seconds based on sensor readings in order to keep the VPD constant. Seedlings seem to love it. Currently there are 3 autos and 2 photos in the box, non-feminized. Hoping to veg the photos while the autos complete.

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Topped the biggest Auto today. All plants are doing fine. Gave them all their first thorough watering yesterday (had been going at it with the spray since the beginning). Vegging now at a target VPD of 1.1kPa (increasing by about 0.05 kPa per week) which translates roughly to 24 degrees C and 62% RH when conditions are completely under control. I included a couple of images of the grow space, which is a work in progress.

Going well! Down to 4 plants because one of the autos grew balls. Ended up waiting a whole 7 days between the autos' first real watering and their second one. I think the first watering is a bit of a shock so it's good to let them recover and give them time to suck up the moisture in the medium and establish a real root structure. All 4 plants have now been topped once each Second watering included an introductory dose of nutes and a soil top-up. Vegging at 1.15 kPA target VPD (about 60.5%RH at 23.5C)

Down to 2 plants, 1 auto (confirmed female - see pics) and 1 photo of still unknown sex. I think the auto will take up the whole space soon enough! She is growing sideways without any training at all, just a big wide ball of healthy leaves. What do you guys think, should I defoliate or train at all? First time with an auto so I'm leaning towards leaving it alone... I rebuilt the control box with fancy new switches which light up. I also forgot to mention that the cabinet locks from the inside with an electrical lock (pictured) which only I can trigger with my phone. 👉😎👉 Also, I now have push notifications, so whenever the conditions drift too far away from optimal, or someone opens the door, I get a notification on my phone. How cool is that! Increasing target VPD to 1.25 kPa this week. Can't wait to see some flowers!

I guess this is week 1 of flowering now that there are clear pistils. I've been leaf tucking instead of defoliating, with some pretty decent success. She is now quite bushy. At some point I accidentally split her stem at the topped node. She didn't seem to care at all. I tied her up to prevent it from worsening but I'm not really worried about it. All branches survived. Upping the nutrients a bit.

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She is very slow to flower... 68 days today and nowhere near completion. I wouldn't be surprised if this is one of those 100+ days autos. Probably Sativa dominant. She is looking good (although a little khaki under the flash). Moved the LED panels to the sides to increase canopy penetration. Each panel is 40 watts so not very much, and having them that close isn't a problem. Watering every 3 days or so and now surfing at a VPD of 1.45 kPa.

Decided to increase the light hours to 20 to increase flowering speed. I've also been defoliating with some great success. She is suffering from some minor light bleaching at the top and center of the canopy, so I have taken measures to resolve that situation. The side lighting is doing a marvelous job at helping the exposed buds develop. Currently surfing at 1.55 kPa target VPD. She is a slow one for sure, but I'm hoping I'll be well rewarded for the wait. Comments/advice appreciated!

Coming along nicely. Still taking her sweet time and putting out pistils like crazy. These buds could be huge if they swell up right! Went a little too hot on the nutes (hence the clawing and tip burn) so I'm dialing it back a bit. I installed a DIY light filter in front of the top LED because it was burning my plant even 20 inches away. Those big-ass COBs are no joke. The target VPD is now 1.65 kPa which translates roughly to about 24.5C and just under 50% humidity. The air is still pretty dry around here at this time of the year, so the humidifier does end up working 10-30% of the time even to maintain these conditions.

Still doing well I think. Top leaves are still a little bleached I believe, despite the light filter I installed. I don't think it's cause for much concern though. Runoff pH was a bit high this week so I've been flushing to get it back down and to help the plant recover from the nute burn. I will start nutrients again this week in small doses. She is frosting up nicely and the buds are slowly becoming thicker. Pistils have barely begun to turn orange. I'm thinking I still have at least 3 weeks to go. Thoughts or comments? Thanks for looking! 👉😎👉

STILL flowering. About 90% of pistils are still white. She is taking FOREVER! She sprouted 105 days ago. Looks like I'll be 120 days total, at least. Weight should be good though! I've capped the target VPD at 1.7 kPa which means roughly 24C and 45%RH. Anything higher would be too dry I think. She'll remain in these conditions until harvest. Thoughts/comments?

Still going. Switched to 12/12 for the remaining couple of weeks. I have come to the conclusion that she is not a "pure" auto. She revegged when I increased from 18 to 20, which suggests some level of photoperiod sensitivity. I have read about super autos which seem to match with what I have... I mean she definitely flowered under 18/6 but it took a long-ass time. Anyways, she's looking pretty rough at this stage with the nute burn, reveg, etc., but the bud is fine and should be plentiful. Next grow will be better dialed in!

Aaand another week. Still 80% white pistils. I've waited this long, I'm not about to cut her down too early!

One more week, I think! There are still plenty of white pistils. About 50% I'd say. She smells kinda like a durian fruit for those of you who've been fortunate enough to experience that. After watering, she also kind of smells like a wet dog, with skunky and citrusy undertones.

Chop day is upon us. She has been served her final meal (a last watering to plump up her cells before drying). She has been stripped of as many leaves as possible. Behold!