this could be the strain from the breeder or she may not having her tap root hit bottom yet, it is almost like she is not getting enough light but shes outside so that rules light out, did you top the plant? she looks healthy in her color so food is not it, i have 2 guesses, 1 from breeder, not strong genetics or just how that strain grows, second root is not hitting the bottom of the pot which would explain the size with some strains when that tap root hits bottom then they will explode in growth. how big of a pot is she is? last you could give more nitrogen with some root enhancer, like house and garden root, clonex, 1 tbl spoon per gallon, or other root nutrients, when the roots build up there is better plant growth. if it was me i would try getting her more light, add more nitrogen with root stuff and wait. also i would check the breeder to see if you can find info on the strain as well as perhaps finding other diaries here on this grow diaries..
that green posion is right where she needs to be, so i would imagine they are on the same food, so perhaps the root has not bottomed out yet or strain from breeder is not strong. keep growing her cause she may just surprise you.