I am planting a sun garden. The plants are zebra grass, gaillardia, coneflower, daisy, keys of heaven, asters, iceplant and echinops ritro.
Are there any plants that I would need to prevent pests from ruining my garden.

The way to prevent most pests is to know the good bugs from the bad ones. [b]Insects in your yard or garden are not necessarily a bad thing. [/b]It just depends on which bugs they are. There are many beneficial bugs that if left alone, will take care of certain bad ones. Howard's Texas Bug book is a good place to start. Also, keeping your plants healthy and soil healthy is the other half of the equation.

Plants that are stressed because of bad soil, improper light or watering will attract pests.

Fertilize with organic materials and spray every 2 weeks with milk diluted at 2 ounces per gallon of water.

Oh, and never use any chemicals for anything.

Never heard or read about spraying with diluted milk. Is that documented somewhere?