Squash

I have some beautiful summer squash, watermelon and pumpkin plants coming up. They are doing so well and look so much better than the rest of my garden. I'm wondering if it's the location of the box? They have morning shade and my other boxes have full sun all day. I'm thinking maybe I should put up something to create a little bit of shade for the rest of the garden. I've got beets, tomatoes, new sweet peas, new corn and lettuce coming up too. I had to replant my corn after Presley ate it:( I am having a heck of a time getting my bell peppers to take off. They start to break through the soil and then die off. I've replanted them 3 times. Any advice??