Yeah, the process of acclimatization/naturalization, when referring to cannabis (et cetera) means growing many - or at least several - generations, selecting parents from each generation that appear to be doing best under the local environmental conditions, growing seeds from those parents, then rinse/lather/repeat. It's like natural selection: critters (animal OR plants) do not suddenly change to fit their environment but, instead, the ones that happen to be better suited for those conditions tend to be the examples of the species that live and thrive long enough to breed, and whose offspring manage to survive said conditions. The actual mutations/changes... Well, they happen sporadically whether there is a need for them or not. Many, perhaps most, of these changes tend to be negative - and those examples, now operating at a handicap, tend not to do well in the Great Procreation Challenge. Others, OtOH... Well, consider the hump on a camel. Looks a bit odd, probably not the kind of thing that a designer would add in for asthetic purposes ( :rolleyes3 ). But the hump allows the camel to survive in conditions that would turn a horse into vulture snacks. That hump would have been just another genetic oddity in many environments, but in desert conditions it was a different story.
You don't seem to have mentioned what strain your current seeds are. If I had to guess - and assumed that all other conditions were the same, my guess would be that you're dealing with two different strains and that the current one has a higher percentage of sativa genetics in it than your previous (successful) strain had. Or it might be that the cool/wet weather is the cause. Cannabis is, for the most part, very much a warm-weather crop. And it doesn't like to "sit around with wet feet" all the time, either - so if your pots are waterlogged, that's hurting their chances. I saw from the image that you posted (thanks for uploading it to your gallery and linking it from there, BtW - off-site image links are verboten here due to potential security concerns) that your soil does not appear to have much (any, lol?) perlite in it. Have you added something to help lighten the soil and provide for good drainage / aeration of the root zone? If not, that - especially if you have been experiencing significant rainfall - could also be a factor.
Six hours of sunlight per day... No, that does not seem like enough. If you're growing a pure indica, or a highly indica-dominant strain, it'll help. Equatorial sativas, lol... not so much. I suppose that, in theory, even one of those could receive enough light-energy in a six hour period. In theory. I don't think that'd happen in practice, because there's an upper limit to how much energy a cannabis plant is capable of processing at one time. And that's in a scenario where the light is very bright and not filtered through clouds and such (IOW, somewhere between the Tropic of Cancer and the Tropic of Capricorn (that border the equatorial zone). In New England, during a cool and rainy Spring / early Summer, though, that seems doubtful.
Like Guy Cavallero, I would say that the plant you posted the picture of looks reasonably healthy. Just small, like it is a fraction of its actual age. My main concern would be the possibility of root rot, if the soil is too heavy and not well-draining. Other than that, lol, hope for cloudless skies and temperatures in the low to mid 80s. And consider choosing strains in the future that have, as part of their description, the ability to do well in uncertain conditions outdoors. I believe that kind of environment is what led to the creation of the Sensi Seeds (also a forum sponsor) Guerrilla's Gusto strain. I will not provide a link, even though it's to a sponsor's website, out of courtesy to Crop King Seeds. But one reviewer had this to say about the strain:
There are undoubtedly more strains that perform well in cooler/wetter climates, and maybe Crop King Seeds has one such in their catalog, IDK. I only remember Guerrilla's Gusto because I bought some (of Sensi's) Jack Herer - and noticed that their Guerrilla's Gusto was approximately 17% of the price of the Jack Herer, lol, which caused me to take a look at it. As Crop King Seeds is a Canadian company - and since Canada is obviously to the NORTH of us - perhaps they have a strain that has gotten good reviews from Canadian outdoor growers that they can recommend for your growing conditions?
A lot of people that grow cannabis outdoors will grow at least two different strains, ones that do best under different conditions. That way, if you have (for example) an unusually hot and dry Summer, you might still have a good harvest... While, if you only grew one strain that was known for doing well in cool/wet conditions, you might have a disappointing harvest. Or vice versa. Insurance, sort of.
Can the act of creating "feminized" seeds lead to a lack of vigor in the resulting plants? Some folks believe so, and I think that - depending on the specific method that was used to produce them - there might be something to this argument. But, no, I do not believe that to be the cause of your issue; it just looks too healthy to have such an issue (small, granted - but healthy). Put that plant on a plane to the Bahamas, lol, and it'd probably turn into a green monster
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