May is the perfect month to plant those slightly tender, late performers such as salvias, penstemons, fuchsias and pennisetums, because they need to develop good root systems before winter arrives. All too often, nurseries sell these late-summer jewels in autumn when they look magnificent. However, there’s not much chance of them overwintering if they’re planted then, because there’s not enough time to get any roots down before the cold weather arrives.
When I go the wonderful Autumn Malvern Show (being held on September 27th. 28th and 29th in 2024) year, I see penstemons galore being carried home in triumph. I know many of them won’t see another year, because they’re being planted at the wrong time. Nurserymen seem to have an obsession about selling plants when they’re in full flower, but that’s partly our fault. We buy with our eyed and flowering plants are the ones that sell, so they load up their vans with plants that will be over in a week or two. Can you blame them? No!
Plant your penstemons in May, if you can get them, and they’ll not only look wonderful in August and September, they should overwinter. I say should, because severe winters can and do see them off. However, penstemons root easily from cuttings taken in midsummer. Find new growth that’s firm to the touch, remove the lower leaves and any flower buds. Plunge the cuttings into gritty compost and keep them out of full sun. Victorians raised their penstemons from cuttings every year, treating them as bedding plants. I have some sympathy with this method, because penstemons tend to look very ragged in winter because they need their top growth for winter protection. They are trimmed back in April, to the lowest growth. They’re also fairly short-lived, most lasting an average of three or four years before they become woody and lose vigour. That’s another reason to take cuttings in your Hartley greenhouse.
You may ask yourself, why bother? Well, penstemons have spires of bee-friendly flowers for many weeks, if you deadhead them. They arrive in daisy season and daisies are mound-forming, dome-shaped plants. They need vertical accents, be it aconitum, red hot poker, verbascum or penstemon, to break up the rolling hills of monotony. There are lots of penstemons on offer, but I still think the best one of all is the claret-red ‘Andenken an Friedrich Hahn’. It’s hardy and very willing to flower. It’s a sultry wine-red, so it mixes well in the border. For many years it was known as ‘Claret’.
This stunner has survived a hundred and six years of cultivation so it’s a toughie. Its robust character might be explained by the fact that ‘Andenken an Friedrich Hahn’ was raised in St Gallen in Switzerland by Herman Wartmann c. 1918. It may not be that cold in St Gallen, because it’s on the Swiss side of the Bodensee, also known as Lake Constance. This is the third largest body of inland water in central Europe and it’s bordered by Germany, Austria and Switzerland.
The whole area is warmed by this huge body of water and warm air also flows down from the mountains. I have visited the botanic garden at Mainau Island, famous for its dahlias and naturalised tulips. The mountain scenery is superb and there are ridiculously cheap flights to Friedrichshafen. There’s a level cycle path right round the lake, some 260km, and it’s on my bucket list!
I thought that Wartman had also raised ‘Schoenholzerei’, previously called ‘Firebird’, because both were introduced into commerce by Alan Bloom after the Second World War. Alan Bloom (1906-2005) told me he anglicised the names to make them more commercially viable in the years following the war, although he didn’t like doing it. However, this red penstemon was in fact raised by Paul Schoenholzer in 1939, hence the name. It’s a cross between Wartburg’s ‘Andenken an Friedrich Hahn’ and ‘Southgate Gem’, a 1910 penstemon raised by J. Bradshaw of Southgate in London in 1910. (This information is from Penstemons by David Way and Peter James.)
More modern penstemon breeding seems to have clustered round the town of Pershore between the 1960s and 2009. Ron Sidwell (1909-1993) was an authority on plums and he could identify any plum just by looking at the stone. Plums were a crucial crop during and after the war and buyers, many based in the Vale of Evesham, would misname their varieties to elevate the price. Cases often ended up in court and Ron Sidwell was the expert witness. His collection of plum stones and drawings is now held by the Badsey Society. I’m not making it up.
In 1948, Ron was giving the task of mapping the weather in the Vale of Evesham area to find out the best frost-free spots for growing plums. They flower precociously early and if the blossom gets frosted, there’s no crop. His map, showing the warmest sites, identified areas suited to plum growing. Ron acquired a property named Bredon Springs in Little Paris on the west side of Bredon Hill. It was a spot he’d found to be extremely mild. However, he wasn’t interested in planting plums.
Ron collected Southern hemisphere plants and he needed a warkm garden for them. They included penstemon species and cultivars and Ron went on to raise the Bird Series from 1960 onwards. They included ‘Raven’, ‘Blackbird’ and ‘Osprey’. ‘Osprey’, a white suffused in pale-pink is the best, although ‘Raven’ is one of the very darkest. Both got AGMs on the recent RHS trial held between 2014-2106. Ron Sidwell can be seen talking about his garden on You Tube. Julie Ritchie knew Ron Sidwell well and her Hoo House Nursery near Tewkesbury sell a good penstemon range in summer. www.hoohouse.co.uk Hardy’s Cottage Garden Plants also have a good range. www.hardysplants.co.uk
Pershore College, where Ron was based until his retirement, also raised penstemon and named them after nearby villages. They include ‘Comberton’ and ‘Bredon’. Edward Wilson (1948-2009), almost certainly knew Ron Sidwell when he was a student at the Pershore College. In the 1990s Pershore held a Plant Heritage Collection of penstemon species. Edward Wilson went on to name fifty penstemons with the Pensham prefix, the village where the nursery was based. Many are stocked by Hayloft Plants and they include Ted’s Purple’, which was named after him, somewhat reluctantly. ‘Plum Jerkin’, named after a local liqueur, ‘Victoria Plum’ and ‘Pensham Just Jayne’ were all raised by Edward.
A lot of penstemons have bright pink, purple or red flowers, but there are subtler ones and I love ‘Stapleford Gem’ for its gloaming-inspired grey-blue flowers. It really stands out in evening light. This came from Stapleford Park near Melton Mowbray in Leicestershire and it’s tall and stately. It has always been confused with ‘Sour Grapes’, but this has darker green foliage grape-coloured flowers. The clone on the recent RHS trail was originally from Margery Fish of East Lambrook manor in Somerset.
The RHS trial awarded many AGMs, including the purple ‘Bodnant, raised by Perhill Nursery in Worcestershire in 1992. ‘Beech Park’, a white and pink, came from the garden of David Shackleton in Dublin. ‘Hidcote Pink’, found in the National Trust’s Hidcote Manor in Gloucestershire, is a superbly strong pink. They’ll all light up your garden, once the days begin to shorten, and the bees love them!