Curator of RHS Wisley Matthew Pottage reveals some top garden plants designer might have overlooked
With plants, I like to have tried and tested them myself or to have observed them for several months – in some cases years – before purchasing them or recommending them to others. Here are a few candidates I will always make space for, or find incredibly helpful in a garden setting.
Gems for shade
While some of the white- and yellowvariegated cultivars of Euonymus may leave you shuddering, E. fortunei ‘Wolong Ghost’ AGM is different. Its rather long, willow-like leaves have a white vein, which makes them interesting but in a subtle way. It is evergreen, and happiest in shade (like its variegated sisters) where it will scramble across the ground, but is also very happy climbing a wall, where it will take shade and make a brilliant evergreen backdrop. It has the ability to reach the top of a 6ft wall in just a few years in fertile soils.
Helleborus ‘Walberton’s Rosemary’ is a real ‘stand out’ hellebore that is not just a good grower, but a showy one. The real show starts after Christmas, when the plant pushes many showy, large, pink flowers for arguably the most difficult two months of the gardening calendar – January and February. The flowers are also quite upward facing. Plant in large numbers for good groundcover and trim off the leaves just before flowering commences to accentuate the full drama of the flowers.
I have a love-hate relationship with daffodils and their loud and difficult to place yellow flowers, followed by masses of leaves that take forever to disappear. However, Narcissus ‘Thalia’ is refined, long-lived, and has a classically elegant white-ivory flower that lights up a shady space, or looks great among low evergreen groundcover.
Pachysandras are often known as the ‘backstop’ plant for the most difficult conditions, usually in dry shade, where they form a neat evergreen mat. However, Pachysandra axillaris ‘Crûgs Cover’ has a little more excitement to offer, in that it has very large leaves with serrations on the margins and showy white flowers in early spring that are lightly scented. It will spread more vigorously in better soil, where it will bring a lush, slightly exotic look to a planting, and its stems can reach up to 30cm high.
We all know and love the Himalayan birch with its white bark, but Betula albosinensis ‘Red Panda’ AGM is a real gem, with wonderful pinky-red bark that peels off in huge sheets. It has all the character, elegance and similar proportions to the white cultivars, and is equally easy to grow, preferring a moisture-retentive soil, and is reliably hardy. Plant several in a group for the full effect of the bark.
Euphorbia rigida AGM is delightful, reaching little more than 30cm spread and only around 15cm tall, with vivid, powder-blue, evergreen leaves that almost resemble a monkey-puzzle tree branch. It flowers in early spring, but is really grown for its foliage. It can be very long lived, but needs full sun and good drainage, and is perfectly suited to rubbly, poor, low-nutrient soil where little else will perform happily. Remove the stems after flowering to the base of the clump to keep it looking its best.
Geranium ‘Patricia’ AGM is one of my all-time favourite herbaceous perennials. This hardy hybrid is both vigorous and sterile (it will not self-seed) and flowers for a long period over the summer. It is best suited to the front or middle of the border, where it will reach just over half a metre in both height and spread. The magenta-coloured flowers are borne en masse and it looks fabulous wandering through roses.
Podocarps are relatively unknown in the UK, and this seems a shame. This evergreen shrub is extremely versatile and has the bonus of seasonal colour. Podocarpus ‘Guardsman’ can be clipped and shaped, grown in sun or shade, and flushes a fabulous vibrant red in spring. It spends most of the summer a dark green in colour, but then turns a rusty bronze in the winter with the added interest of yew-like berries. Growth is rather slow, however, and older plants will only reach 1.5m after around 10 years.