Alpines are normally associated with spring flowering but there are many which flower during the summer and add a zingy splash of colour to the garden.
Gladiolus flanaganii is a beautiful gladioli hailing from cliffs in the Drakensburg Mountains which border South Africa. It is not as large and brash as the typical florist’s version, only up to 30cm tall and with fabulous, rich red flowers. It is also known as the suicide lily as plant hunters have had a history of risky attempts at collecting or photographing them! It needs a sunny, well drained spot and the bulbs are best kept dry in winter, ideal for pot culture.
Pelargonium endlicherianum from the mountains of Turkey has neon pink flowers. The top two flower petals are quite large and when the plant is in full bloom look a bit like a cloud of vibrant butterflies. It is the only reliably frost hardy pelargonium, but needs good drainage and a sunny spot to thrive. It benefits from a dry rest in winter.
Campanulas are another summer favourite, extending the season of interest in the alpine zone. They come in a lovely range of blues, purples and whites with the occasional pink too.
An absolute star of the alpine zone is campanula garganica ‘WH Paine’. This grows in cracks in the walls in the alpine landscape and creates incredible purpley-blue mats on the rocks in summer. It’s easy to grow and is very reliable; it also is well behaved and doesn’t take over!
Ourisias are gorgeous, unusual little plants which originate from the Andes in Chile. They grow on damp cliffs in the wild and are covered in flowers at this time of the year. They can be a bit of a challenge to grow and often suffer from grey mould attacks. They are doing very well in the alpine house here at Harlow Carr and you can see a number of different varieties flowering including the species microphylla with its profusion of pale pink flowers and the polyantha hybrid ‘Cliftonville Scarlet’, a rich, orangey red. They do best in the alpine house, where you can monitor the conditions and give them great ventilation.
There are many hardy succulents flowering in summer with the most intensely coloured satiny flowers. Delospermas originate from South Africa and are an excellent choice for a hot, dry area of the garden. They come in a variety of sizes, the prostrate, neat mat forming ‘Gold Nugget’ which blazes with bright yellow flowers is a great spreader and is useful to hold a dry bank together. ‘Ruby Coral’ is more shrubby, reaching up to 20cm high and quite branching with slim fleshy leaves. The flowers are produced in a neon reddish orange, almost as lit from within like the glowing coals of a fire.
Lampranthus roseus, the mini ice plant also comes from arid areas of South Africa. The large spidery daisy-like flowers are about 4cm across and a hue of the most eye burning, vivid pink. The fleshy leaves are borne on quite longish, stiff branches and it looks fab growing out of a hot, sunny wall. Come along and see some hot colour for yourself!