The stars of the Christmas bouquet this year were the stems of luscious Penstemons, which I have scattered in various beds around the back yard, and with which I am totally enamoured. They are largely North American plants, and for our gardening purposes split into two different groups. There are a number of more or less dwarf species which are very valuable for edging a border, or for an old fashioned rock garden.
However, the more commonly found forms are the border perennials that are sometimes called the “queens of the summer border” much loved for the prolonged flowering season and their hardy reliability. They are very easy plants, at home in any soil as long as it is not too damp, and will thrive during the hotter summer months. Many species are to be found in arid areas of North America, and Americans tend to think of them as wild flowers, which perhaps explains why the hybrids are more popular in Europe than they are in their own country.
One of the reasons I like these guys is that you can easily bulk them up yourself – they are very easily grown from autumn cuttings, grown under cover over winter and planted out in spring. That allows you to be generous with the planting size you can go for, and believe me, a bed of ten or more of one variety looks absolutely stunning.
There are many, many varieties on the market, and I am not sure that they are all correctly named. I have some catalogues where the owners are proudly stating they have the “true” form of a named variety, alongside that of other nurseries, where the same claim is made, and the plants are quite different. It might be that the best thing is to see them in flower in your local garden centre and decide on that basis.
‘Blackbird’ is one variety there is some discussion about. As I understand it, this has relatively small deep maroon flowers, held delicately on dark stems, making it a great cut flower. It grows to just over a metre high, and will spread almost that wide after a few years. But there is another ‘Blackbird’ being sold in New Zealand, and the “true” form, with flowers that are nearly as deep but are much fatter and are borne on a plant that is much stumpier in growth.
Another with slightly wiry stems is the glorious ‘Drinkstone’ which has rich reddish-pink bells drooping gently with large stems filled with colour. When at its best, the large stems are covered with flower making this a great variety for picking.
One of the older varieties which have stood the test of time is the subtly coloured ‘Hidcote Pink’, named after the lovely English garden. It has medium sized flowers, pink with dark pink veins in the throat. It clothes its stems well with bloom and is a hardy reliable doer in the garden.
If you were picking a few Penstemon to grow with an eye for picking for the house you would make sure you had ‘Snow Storm’. It has pure white bells in heavy panicles on strong stems and is a fabulous addition to the border and is probably one of the best white flowering perennials for summer. It is medium seized at about 80 cm, and has a bushy growth habit.
If showy plants are more you style, and you are a fan of falsetto singing or disco music you will not be able to resist ‘Maurice Gibbs’, with his cerise pink to red flowers with a bright white throat. On the other hand, if you are feeling more sombre and sober you might want to go for the darkest Penstemon you can find. In that case you will be looking out for ‘Raven’. As well as being one the darkest of all the varieties, it is also one of the showiest, with dusky, purple flowers that flare just enough to let you see a white striping on the throat. It is not one of the huskiest growing of the Penstemon, but it is surely one of the prettiest.