Jack plants and blueberry

I have two jack herre plants the one in front is the oldest of the 3 plants but does not seem to be growing like the other two, I have given grow big in my last water. Any thoughts on what is going on?

What is your soil? When I grow in happy frog with extra perlite I litterally only feed veg nutrients one time a week before flip, otherwise water or water/cm, then veg again then 50/50 veg/flower then flower. Happy frog is not considered a hot soil. Overwatering/underwatering and overfeeding in veg are the 3 most common mistakes. I bought the Bergman’s complete set. The seedling furt is useless in a cannabis soil. The veg nute isn’t used more than once a grow unless you don’t have a cannabis soil. Based on that. I wouldn’t have fed anything yet l. Depending on your soil. Your soil is also quite dry.