Hi Murkerr, i'm no export on autos or indoor and have very little experience with weed in general but am a keen gardener/plantsman in general, and would say that they it does seem a little on the small side. I'm also UK based and three weeks (22 days) into my first grow and my plants are similar or slightly bigger. See here for more:
https://www.autoflower.org/f6/outdoor-uk-first-time-journal-ref-34201.html. Some of the moderators maybe able to give you some better opinion, but I would ignore the 'rules' a little bit and do whatever the plant responds too at this stage. If its reacting well to being in a greenhouse/natural light, then let it have as much as it can! etc. You want as much upward growth as you can get now so try and get the little lady to put on some weight. A little bit of nitrogen based feed might help too. Good luck!
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Hi Murkerr, i'm no export on autos or indoor and have very little experience with weed in general but am a keen gardener/plantsman in general, and would say that they it does seem a little on the small side. I'm also UK based and three weeks (22 days) into my first grow and my plants are similar or slightly bigger. See here for more:
https://www.autoflower.org/f6/outdoor-uk-first-time-journal-ref-34201.html. Some of the moderators maybe able to give you some better opinion, but I would ignore the 'rules' a little bit and do whatever the plant responds too at this stage. If its reacting well to being in a greenhouse/natural light, then let it have as much as it can! etc. You want as much upward growth as you can get now so try and get the little lady to put on some weight. A little bit of nitrogen based feed might help too. Good luck!