DUDE! how did you get to "bad DNA".... that's some crazy talk lol.
Personally from the looks of the plant I would have to say it was aliens that have caused the problems. I see some Phaser and heat ray damage so maybe you run high temps with your HPS, high temps will attract aliens sooner or later and you should consider reducing the heat.
Some possible fixes to your problem are; using a cloaking device, putting up a force field around the plant or if funds permit maybe even get a laser cannon and stand guard over it!
Or if those don't work you could just wait a bit longer for some stretch to happen, 22 solar cycles is not long, I'm guessing that after more solar cycles she will get taller..
Stay stoned....oh so very VERY stoned....
Stunted Sanity