Soil:  Penstemons, by their very nature, will thrive in almost any conditions but most of the European Hybrids prefer an open and sunny position in well drained soil.  Drainage is important, particularly if you are leaving the plants to over-winter in a border, as they really do not like the crown of the plant being constantly wet.  I lost a good number to a very wet winter in 2000/2001.  Some penstemons will tolerate shade and a few positively enjoy it.  I will attempt to classify each penstemon as I update its page.  

For new plantings of penstemons in a border make sure that you dig the area thoroughly and if your soil is not naturally free-draining include large quantities of grit and sharp sand.  Include a good fertilizer or good organic material but bear in mind that drainage is more important than fertilization.  For existing plantings ensure that the soil is forked well around the plants in spring and apply fertilizer for the new season, pelleted chicken manure or blood/fish/and bone meal is good.  I tend to loosely mulch with compost from the garden bins in the autumn which gives some help in protecting the new shoots as they appear.

Pruning:  You cannot expect to be a tidy gardener where penstemons are concerned!  Removing seed heads during the growing season, with some exceptions where the seed heads will improve the look of the plant (e.g. Garnet), will help to encourage more flowers but do not cut back the flowering stems in the autumn as they help to protect the crown of the plant and its new shoots from the frost.  When new shoots appear at the base all danger of heavy frost is passed then you can cut most penstemons well back being careful not to damage the new shoots.

Planting:  Take account of the spread of each penstemon, especially in mass border plantings, and be careful not to introduce pest affected plants into established plantings.  Many penstemons, especially those marked as 'patio varieties', are suitable for pot culture and are particularly colourful in a small space.

Replacement:  The persistence of penstemons varies from one variety to another and experience will show you when to remove older plants and replace them with younger ones.  The best way to assess the potential of plants is to look carefully at them during the spring when the vigour of the new growth can be assessed.  Some plants become very 'woody' as they get older and should be replaced when this happens.  Of course any cuttings that have been grown for the next season which are not needed can be passed on to friends and neighbours to encourage their spread.

Cut Flowers:  Penstemon Glaber is one of the best and will last for anything up to a week before the flowers begin to fade and drop off.  Experiment, if you can bear to cut the flowers off!

If you find that I am innacurate in my descriptions or remedial action please let me know.  I will not be offended.  Honest!!