I have a few Cherry AK-47 plants that are 1 month into veg. They have purple stems at the base and through the beginning of branches and seem very 'wood' like. I am afraid that they won't get any bigger. The leaves are big and green and look very healthy. Only once I left the nutes and fresh water in a day longer than I should have. So have I stunted these guys permanently? Many thanks!
Most likely a Magnesium or Phosphorous deficency. I've had this happen to me a few times, but only on plants that I neglected or didn't take care of. You didn't do any permanent damage, but make sure to feed those guys!
i've had purple stems and petioles in veg which is ok but if the actual leaf is purple that early, the above poster is right on.
its typically normal for some strains to have purple stems and leaves. You mostly go off of what the leaves tell you for deficiencies. Magnesium and phos deficiencies are easy to detect in your leaves and you can even find a guide on the net showing pictures of plants with certain problems and go off of what it looks like.