Suchie,
Typically, penstemons rot in our rich, loamy soil in Madison, Wisconsin. Donald has a beautiful raised bed where he has amended the soil to be light and sandy and penstemons grow beautifully there. Penstemon murrayanus lived for about a month in our soil and even bloomed, then it promptly died as did several other Western penstemons. Many people in Wisconsin have poor sandy soil, which is perfect for these plants, but we live on land that used to be a university farm (but it's great for growing salvias.) I have had some luck growing these salvias in containers and then you can create the soil that you need and control the water that they require (I have read that they like deep, infrequent waterings.)