Hi Monica they do get direct sunligt. My backyard faces east so they get direct sunlight from 8am til 10ish but its not intense. However, I also hang my sun lovers on the fence (those plants are not in the shadow of the gazebo). The vandas are in the lower section so they are protected, it took a lot of trial and error

I do not add fertilizer to my sprinklers, just plain old city water. I use a sprayer with diluted granular fertilizer and spray the roots after they are watered. I find this effective in reducing waste