Living in Utah, they are amazingly easy for us to grow. All we have to do is usually scatter seeds and let nature do all the work and watering. For transplants, all one needs to do is dig and water. And yet most of the population tries to make their gardens look like the green, fat, lushnesss of the gardens of the eastern US and Europe.

Try P. cyananthus or Wasatch Penstemon. It can take more mesic conditions if the soil is fast draining.