okay so now that the seedlings are growing fairly well (only one has died that I know of) there's the issue of which ones to keep. you only get to keep one per square pod. which is obviously complicated considering that many of the pods have three or more perfectly good seedlings in them.
so first, why are there so many? honestly I was under the impression that seeds were much less successful than they've turned out to be. I thought seeds were more of a numbers game. and that's turned out to be both true and false. the germinating (sprouting) seeds battle one another for resources like water and nutrients in the soil so it's theoretically unlikely that more than one per pod makes it above ground. I was almost sure that I'd sewed no more than 3 seeds in each pod but it turns out that a) I was wrong - a lot of pods have 4 seedlings in them and b) the success rate of these seeds has been so high that any more than two would have been overkill.
*an interesting note: it seems that the lettuce acted pretty much as I expected, with only one seed becoming a seedling, where almost every seed has germinated successfully. not sure yet if that's a result of the seeds or the plant itself.
anyway, now that we have all these seedlings we have to thin them (i.e. kill some of them) so that we're left with only one per pod. to be honest it's pretty upsetting that this is the way it works but I guess when it comes to crops you don't get to be that precious about life. either way I'm going to try my best to avoid this kind of waste going forward.
so how do you decide who stays and who goes? how do you tell who the most viable candidate is?
well here's another thing that doesn't work the way I would have expected. I would have thought that the tallest seedlings are the most successful. but those actually aren't the ones that you want.
imagine it like creating a video game character. you have 10 points to spend on attributes. the attributes you can choose are height and resourcefulness.
now imagine that resourcefulness is the only quality that you want from a seedling and you have a lineup of 10 of them. how will you tell who's the most resourceful one? well resourcefulness isn't a visual characteristic like height is, but you can use some pretty simple deductive reasoning to work out where the seedlings spent their points. which is to say that if a seedling spent all its points becoming tall, you know that it's not very resourceful.
the way that this actually translates to real life is that seedlings that are suffering to gather nutrients underground, at the root level, spend all their energy growing tall to compete for sunlight above ground. so they're spending all their energy in the short term trying to survive rather than spending it becoming a stronger seedling that's more likely to survive outside.
so the tall ones go. you just cut them right out of the soil. and you keep the ones that are the most compact viable seedlings (where viable just means not dead looking).
the issue that I have right now is that I have no baseline for how tall a seedling of this age should be. so the seedlings that are most compact (in comparison) now might just be runts and the ones that are tallest might not necessarily be struggling - they might just be earlier growers.
I'm going to need to wait a couple more days until I can get a good idea of what the actual situation is in each pod.
for now I'm working on solving the other issue visible in the photo - the fact that the seedlings are leaning so heavily towards the sun. I've rotated them 180 degrees so hopefully they grow in the other direction - eventually leading to straight, strong seedlings. I imagine that the rotation will also give me a good idea of which ones grew too tall too quickly as they'll probably have a hard time growing in the other direction if they're already spent all their energy.