I'm using a VPD growing chart to keep my newly planted seedlings in the VPD "sweet spot". The VPD grow chart (downloaded from dimluxlighting.com) shows a VPD range for propagation and "Early Veg Stage" of 0.4-0.8 kPa and then shows a VPD range for "Late Veg / Early Flower" at 0.8-1.2 kPa. Here is my question: what determination, criteria, etc do YOU use to tell when your indoor autoflower plants move from the "early veg stage" into the "late veg stage"? I'm not clear on when you can tell or decide that a plant is into the "late veg stage".
first how do you measure the kPa .....2nd you are way overthinking this in most auto strains the veg flip to senesce is barley noticeable depending on strain, the average grower barely notices except t for young flowers 2-3 weeks after the seedling stage I like to grow thc auto bomb(for over 10 years) a white widow type strain that offers me 8 eight days of veg in that time I can clone even air layer her of to another pot other strains like power plant auto, thats not gonna happen again its all strain dependent IMO get to know your strain good luck
I measure the kPa with the probe from my grow controller. I also have another monitor device that I'm not using for a vegetable garden greenhouse any longer so just for the hell of it, I have that in the tent as well. Guilty as charged on overthinking it. It's part of my nature to delve more deeply into things than most people would. It's in my wiring. Maybe if there's no real difference or separation in stages in autoflowers, no significant "Early Veg" and no significant "Late Veg" stage, then averaging the two stages and running the entire time until Mid/Late Flower at between .60-1.00 kPa (VPD) might be the best way to go. I might try just doing that.
What happen to the good old days ? Plant the seed let it grow . Plant veg to its ready and starts making pre flowers . End of veg. Who could tell you how long they will veg ? Pre flowers just start to form . Autos sizes are different 6 inches to 4 feet
almost exactly 28 days from sprout. If they were photos, that is when they look like they are ready to flip. Ruderalis is truly a weed that is going to flower and there is really nothing you can do to stop it.