Penstemon
By Sjw
gloucestershire,
United Kingdom 
I have some penstemon that are getting rather leggy and woody at the base, they have flowered, I have removed the dead flower stems. Can they be pruned hard back into the dead wood and will they continue flowering all summer, the first flush of flowers were good but now seem to be very sparce.
30 Jun, 2009
Answers
Try also taking some cuttings of none flowering shoots to replace the parent plant. Now is a good time to do this.
30 Jun, 2009
I find that my cuttings root better in water, rather than gritty compost, for some reason. Just a thought for you! You could try both ways and see what works for you.
30 Jun, 2009
as far as i know, yes, bcos they seem to be quite resiliant, reliable plants. Try treating them to a dressing of new topsoil once you've cut back, or feeding them a little?
30 Jun, 2009