Perfect pennisetums
If you’re looking for a showy ornamental grass it’s hard to go past these
Pennisetums are among the most fabulous of high summer-flowering grasses. Their common name of fountain grass aptly describes their habit of producing masses of fluffy, immensely tactile flowers with great enthusiasm in a range of rounded and cylindrical shapes and in colours ranging from purplish-black through reds and pinks to beige and white. However, like many fabulous performers they can be a bit fussy, and so correct siting is key to long-term success.
There are about 80 species of fountain grasses which are native to warm, temperate and tropical parts of the world. However ,only a very small number are sufficiently hardy to make reliable garden plants here in the mild and damp maritime climate of the UK.
While the foliage of pennisetums is not very exciting, it acts as the perfect foil for the fabulous flowers, which seem to almost explode from among the leaves in a veritable ‘fountain’. This effervescent effect is what makes pennisetums so useful as they offer almost perfect partnerships for a huge number of summer-flowering perennials.
Pennisetum thunbergii ‘Red Buttons’ is nearly always the first fountain to come into flower – often around midsummer – and its small, rounded, red flowers sit daintily above the bright green foliage that look great with so many early perennials. Pennisetum alopecuroides can fail to flower altogether in the UK climate, but has actually produced some great varieties that perform beautifully. ‘Hameln’, for example, was selected for its comparative hardiness and while the flowers aren’t the largest, it’s very free flowering, compact and reliable. Varieties such as ‘Cassian’s Choice’,
‘Herbstzauber’ and ‘Red Head’ are all good performers in the UK and share the typical rounded habit and large, bottlebrush-like flowers that appear to double in size and colour complexity with the morning dew.
‘Dark Desire’ is the most recent selection, whose large flowers change from red through many shades of charcoal-grey to almost black as the season progresses. Pink flowers come from Pennisetum
orientale and its selections. The species itself has a soft pink flower but can be a little delicate in the UK. ‘Shogun’ seems hardier with soft pink flowers, while a little taller, ‘Karley Rose’ has flowers of a more strident hue. For creamy-white flowers Pennisetum
macrourum ‘Short Stuff’, with its fire worklike, upright-pointing, narrowly cylindrical flower heads, was selected for its compact nature and willingness to flower in the UK.
Pennisetum villosum has a more lax habit and is possibly the least hardy but has the largest fluffy, creamy-white flowers and is deservedly always popular.