That could be it cause I've had some weak growth , I'm at 3 quarter right now. The new thing now it went from yellow dots , to brown and very small. Only one bud shoot has them and very small, I'll add photo. I have started to spray the foliage as well like you did maybe that helps. Also do either of you guys use the thrive alive green as a foliage spray? Says it could be used once every two weeks after transplant. Might give it a go cause my growth has been kind of weak for day 28.