BOLD PERFORMERS
Their striking appearance may belie a tender nature, but a long, colourful display earns Hebe speciosa hybrids a sheltered place in the garden
AMONG THE GLOSSY leaves of a dense shrub, spears of vivid red flowerheads stand proud, gently bobbing in the breeze. Fulsome and whiskery, these are the spectacular blooms of Hebe speciosa, which put on a show that lasts well into the autumn months. Its bold appearance is deceptive. This evergreen shrub is a tender plant that thrives in mild weather and sheltered spots. It is particularly suited to warm coastal gardens, as its waxy foliage withstands both wind and salt spray. However, given the right growing conditions, this big, showy beauty is worthy of a place in any garden. There are altogether 100 species of hebe, of which H. speciosa is not only the most dramatic but also the largest. It can reach 5ft (1.5m) high, growing vigorously, with its lush, shiny leaves reaching 4in (10cm) in length. Rounded at the tip, they are almost egg-shaped. Pairs of opposite leaves are set in four rows, forming a cross viewed from the tip. It is a handsome shrub, with a rounded habit and foliage reaching down to the base. The large clusters of H. speciosa’s magenta flowers are up to 4in (10cm) long
at the shoot tips. These spikes of flowers, more accurately called racemes, grow in the leaf axils at the upper end of the stems, on new growth. The individual flowers are small, with four petals forming a tube at the base. They open upwards from the base of the spike, often changing colour as they age, usually becoming paler. This has the lovely result that a raceme of flowers may display a two-colour effect. The flowers are attractive to insects, especially butterflies. Pollinated by insects rather than bees, they have no need of scent. It was the large glossy leaves and showy flowers that made H. speciosa the focus of gardeners in the middle to the end of the 19th century. Many hybrids were raised at this time. These remained popular in the 20th century, but then fell from favour, replaced by hardier plants. However, even if only regarded as summer residents, H. speciosa hybrids are worth trying.
A long journey
A native of the mild North Island of New Zealand, Hebe speciosa was discovered in 1833 at Hokianga. This is a region at the north tip of the island, where frosts are rare and the average winter temperature is 7°C. It does occur wild further south, in cooler climates, but always near the coast, where frosts are absent. Its native name is Titirangi, the Maori name for the area. In the wild, it flowers for a month or so in summer and again in winter, but in cultivation it tends to flower throughout summer until stopped by frost. Today, H. speciosa itself is rarely seen in gardens. Instead its place has been taken by its hybrids created by crossing it with other hebe species. This has produced plants with the large flowers of H. speciosa plus improved hardiness. Most hybrids produce their showy flowers from July through to October. The majority will reach 40in (1m) high and wide in mild areas. In coastal areas, they have the potential to exceed this average height. However, they are frequently damaged in inland gardens and suffer frost damage in the average winter. The cultivars are divided by colour into purple, red and lilac and pink. There are also some with variegated foliage. One of the most popular of the purple hebes is ‘Franciscana’. A short, mounded plant, with stubby leaves, this is frequently sold in full bloom for autumn pots and window boxes. The flower spikes have showy, unusually large, violet-blue flowers. A hybrid of H. speciosa and H. elliptica, it is among the hardier of the speciosa hybrids. It is generally accepted that it arose as a seedling in Golden Gate Park, San Francisco, and was named in 1943. However, the same cross has occurred
several times, including in the UK. ‘Blue Gem’, for example, is now considered the same plant as ‘Franciscana’. This was allegedly a seedling raised in the UK in 1868. It is a perfect seaside plant, tolerant of salt spray. Although it is a neat, mounded shrub, it often well exceeds the average height of 1m (3ft) when grown against a wall or windbreak, where it can double that height. Moderately hardy, it also comes in a variegated form that is often sold for winter pots and box displays.
Reds and pinks
Popular red cultivars include ‘Paula’, a compact hebe, with narrow, deep green leaves and upright, 4in (10cm) spikes of rich pink flowers all summer. It reaches a height of 30in (75cm). Another is ‘Simon Delaux’, an old hybrid of French origin, with large leaves and flower stems. Upright in habit, it produces its crimson flowers through the late summer and autumn until stopped by frosts. One of the hardiest of the lilac and pink cultivars is ‘Great Orme’. This narrow-leaved hybrid is a good plant to start with. The pink flowers, quickly fading to white, are produced for a long period in summer on their slender spikes. It reaches a height of 5ft (150cm).
Early bloomer
The first hybrid, raised in 1848, was ‘Andersonii’. This is a large, upright shrub reaching 6-9ft (2-3m) in height. Its narrow leaves are mid green in colour with pointed leaf tips. It also comes in a variegated version with irregular greyish white margins that match the pale purple to lavender flowers perfectly. The 4in (10cm) long spikes of flowers arrive earlier than most, in midsummer, with narrow spikes, up to 10cm (4in) long, of pale purple flowers that fade to lilac. It is thought to be a hybrid of H. speciosa with Hebe salicifolia.
Cultivation and pruning Although they are not fussy about soil types, these hybrids do not grow well in wet soils. Clay soil should not be a problem, provided it does not get waterlogged in winter. Rich soils may encourage soft, vigorous growth that can reduce the lifespan of the plants and make them less able to survive cold winters. Hebe speciosa and its hybrids are pruned in spring. This removes stems damaged after winter, or reduces their size. They will generally send up new shoots. Propagation Hebes can be grown from seed, but are better propagated by cuttings, which root readily and easily. This is the only way to propagate named cultivars. Although cuttings can be taken at any time the plants are growing, the best time is in mid-late summer. If taken then, they root readily, and the plants will be well rooted by winter so there are strong young plants to put out in spring. The cuttings should be taken of young stem tips with three or more pairs of leaves. Small-leaved hebes should be taken with more leaves