straggly penstemons?

Hi, I planted penstemon delft blue for the first time this spring. There is loads of folliage and long straggly stems but no flowers. what am i doing wrong? I was led to believe they were really easy to grow and produced a great display.

 

Moss, the first rule of gardening is, be patient. If you have lots of green growth, the odds are the soil is acid. What I would do is start feeding the plant with a half strength tomato feed once a fortnight, this should help it flower next year.

 

Thanks for your advice. I'll try that.

 

Is it getting enough sun?

 

You may have a point. When I first planted it was getting plenty of sun but then the borage and mint grew and has somewhat shaded it from the midday sun. Moving it to a more suitable spot may be the answer?

 

Should I cut the stems back then replant in a sunny location or just leave them?They are all over place quite messy.

 

I would leave it until the spring now.