Learning is good, it is what keeps me interested in this mischief. If I may, I think the lesson here is that growing healthy plants in solo cups is pretty much a dedicated hydroponics exercise. At least it has to finish off that way. A solo cup of soil does not contain enough nutes to finish a happy plant.
I feel like I'm having a decent time in soil *so far* but I'm also only 3 weeks in so there's a very real chance things may take a turn for the worse once she gets a little further along. I'm wondering if it may also have something to do with the water holding properties of soil vs coco, as from what I can tell a lot of the soil examples seem to look overwatered even when they really aren't. Idk just something I've noticed watching everyone in this grow. I've also gathered that this strain may be particularly extra hungry, and seems to like more of a "indirect" less intense light. Perks of my seeds taking a trip round the world, I've been able to see what has and hasn't worked for everyone along the way while I waited for mine.Learning is good, it is what keeps me interested in this mischief. If I may, I think the lesson here is that growing healthy plants in solo cups is pretty much a dedicated hydroponics exercise. At least it has to finish off that way. A solo cup of soil does not contain enough nutes to finish a happy plant.
Or so goes my current theory, with exactly zero finished solo cup grows. So, still stoner theory, and we know how that goes sometimes.
I am seriously new at solo mischief, but I think I have learned two things so far. First, you have to obtain adequate runoff at least every day if not every irrigation if you use salt nutes. If you let salts build up, shit will happen and quickly.
I wonder if doing a root pruning and replacing with fresh soil would mitigate this, perhaps in early transition so as to cause dwarfing much in the same way as @arty zan's process of repotting around the same time the plant shows sex.I am seriously new at solo mischief, but I think I have learned two things so far. First, you have to obtain adequate runoff at least every day if not every irrigation if you use salt nutes. If you let salts build up, shit will happen and quickly.
Second, especially as plants get bigger, they use up nutes/liquid remarkably quickly, and if you let them dry out, shit will also happen quickly.
What these two lessons (I am sure there are more lurking for me) mean for me so far is that getting the fertigation/irrigation sequence sorted can be a serious pain in the ass. My largest plant is not happy, and as of today I think I have figured out why. The problem seems to be that that one solo cup is so tightly plugged with roots, that the nute mix builds up in only six seconds to the point that it overflows the cup, losing the nutes that would otherwise result in needed runoff. None of the other plants are doing this, at least not yet. The difference in infiltration of nutes between plants is dramatic. The large plant requires multiple minutes of infiltration time before the nute mix all penetrates the surface of the coco. All other solos are clear of pooled nutes in a fraction of the time.
In order to fix this issue, I have now set the timer up to do four fertigations per day, each consisting of three six seconds bouts of pumping with ten minutes between them. Six seconds is enough to fill the solos to the brim, but not overflow much, and ten minutes is more than enough to make sure that it has a change to work into and through the problem cup. The jury will be out for a couple days as to whether this fixes things.
In future, more headroom above the coco, and more perlite (currently only 20%) might help this issue, but I expect that the issue of nute penetration of tightly root bound pots will always be a problem for solo grows where plants get big. Stoner theory so far though, so feel free to ignore.
There is one way to find out, but it won't be me that tries it.
I expect that, at least with autos, this degree of manipulation in a solo cup will not accomplish a lot. If you pruned an auto's roots enough to make room for new soil, I expect that the plant will be stunted or at least will use up a chunk of the limited available time recovering. I think the answer (if I have asked the right question) is to figure out how to accomplish the necessary amount of runoff reliably even once the cup gets plugged tight with roots. Next time around, I will double the perlite, and increase the headroom left in the solo cup above the coco medium, the combination of which should at least reduce the problem a bit if not eliminate it. 
Nice blaze session spot outside your tent
