Shabedue some of the people who post about ruderalis hybrids swear by them - easy to grow, some strain relatively potent, short, easy, less headaches, fast bud from seed to harvest, etc. I'm growing a Taiga by Dutch Passion as my first autoflower (auto AK was out of stock), I had it in 18/6 with 11 hours under the 1000W HPS and 7 under a 125W HO floro 10,000K and it's starting to grow flowers now under 12/12 (too big to move from flower to veg room in a 5 gallon bucket).
On the downside they will be less potent and produce a smaller harvest than a full size indica or sativa grown in the same place.
That being said, I've got 2 big laughing that I vegged to 16" and only stretched to 18" and 19" that produced 2-3 oz each of very potent bud. So short plants can be good producers, the autoflower growers often say that they get an ounce per plant.
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" I want a hardy auto-flower but I'm worried about the potency."
Auto AK47 gets the best reports for potency. I know nothing about Dutchbreed or Lowryder Mint.
http://www.cannabis-seeds-bank.co.uk/lowlife-seeds/lowlife-automatic-ak47-autoflowering/prod_427.html
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"I've read about some instability in ruderalis hybrids."
What type of instability? Sexual - hermies? The biggest threat to hermies, other than piss poor breeding are feminized seeds. Check out this thread, I'd advise regular seeds over feminized.
https://www.rollitup.org/seed-strain-reviews/182247-feminized-seeds-hermie-test-14-a.html
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"They claim a high THC content 17-23% "
I always wonder "17-23% of what? The weight/volume/mass of cured bud? The weight of the bud removed of all water? The weight of the THC comared with the resin in the trichnomes stalk plus the resin that makes up the head plus the gland(s) inside the trich head that makes the THC? And how did they come up with the measurment - gas spectrometer or pull it out of their ass?
Forget that bullshit, all marketing, look for smoke reports and experience from growers.
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