Why are my Haze #1 feminized plants getting too bushy?

I’m growing Haze #1 feminized seeds, and I’ve noticed that some of my plants are getting very bushy. It’s hard to get light to all the buds, and I’m worried about mold and mildew forming in the dense foliage. What could be causing this issue, and how can I keep my Haze #1 plants from getting too bushy?