Saturday, November 19, 2011

The Protea Family (Proteaceae)


!±8± The Protea Family (Proteaceae)

The protea family (Proteaceae) includes a wide range of ground covers, trees and shrubs that often make superb garden plants. While some of the species are frost-tender, they are in all other respects remarkably resilient plants that often thrive in situations where others would rapidly succumb. Poor soils and hot dry positions that scarcely seem capable of supporting life are often ideal for Proteaceae. If any plants could be said to thrive on neglect the proteas can.
Proteas (the term is often used collectively as well as for the genus itself) are a variable group. Indeed, the family was named after Proteus, a Greek god capable of changing his shape at will. It includes some 60 genera and 1400 species of Southern Hemisphere plants, the bulk of which are native to southern Africa and Australia with the remainder coming from South America and many of the Pacific islands, including two species (Knightia excelsa and Toronia toru) from New Zealand.
There is an enormous variety of foliage among the proteas. It is almost always evergreen, but may be needle-like, as with many grevilleas; long, narrow and serrated like that of Dryandra formosa; or rounded and leathery like the leaves of Protea cynaroides. Some genera, particularly Leucadendron, include species with brightly coloured foliage, the intensity of which varies with the season. Leucadendron stems retain their colour for weeks when cut and are an important part of the cut flower industry.
Protea flowers are composed of clusters of narrow tubes that are often curved. These 'spider' flowers are seen at their simplest in the two native species and some of the grevilleas. In many cases what appears to be the flower is actually a bract of brightly coloured leaves surrounding the true flowers. The most impressive example of this is the dinner plate-sized flower head of Protea cynaroides. The flowering season also varies; many proteas and grevilleas flower in winter, while leucospermums tend to flower in summer. With careful selection it is possible to plants in flower all year round.
The flowers often contain large quantities of nectar that many birds relish. Some species have very sticky flowers that will trap visiting insects, especially bees an this slightly sinister side of the flower appears to serve no particular purpose.
The South African and Australian Proteaceae tend to be at their best in warm, dry conditions and often thrive in coastal areas. Inland, unseasonable early and late frosts often kill all but the hardiest specimens. The South American genera tend to be hardier and prefer somewhat damper conditions. Embothrium in particular, can withstand hard frosts and is grown over most of the country. But where winter temperatures regularly drop to -6°C or lower, most proteas require frost protection.
Cultivation
Other than a suitable climate, the key to success with proteas is establishing the right soil conditions. The protea family is mainly adapted to mineral based soils that drain very quickly and which often have low nutrient levels. These soils tend to be moderately acid and are often especially low in phosphates.
Good drainage is absolutely essential. Rich loams and heavy clays do not make good protea soils. If you have a heavy soil do not try to improve it by adding sand or shingle as this will often make the problem worse; the soil binds with the sand and shingle and sets like concrete. Instead add more humus. Proteas would not appreciate the rapid burst of nutrients from a rich compost so the humus used should be fairly low in nutrients. Natural leaf mould and rotted pine needles work well. To avoid these materials compacting down into a poor draining thatch, incorporate about 50% fine shingle grit by volume and combine the mix with the existing soil.
Most proteaceous plants come from areas with low rainfall or where the rains are strictly seasonal. Many are coastal plants although most of the South African genera include alpine or sub-alpine species. Knightia from New Zealand and Embothrium from Chile are exceptions; they usually occur away from the coast, in areas where rainfall is quite high and not seasonal. Nevertheless, they still demand excellent drainage.
Although proteas are remarkably resilient and not difficult to grow there seems to be some common myths regarding their cultivation. Like most myths these have some basis in fact, but they can be misleading.
Myth 1: feeding proteas will kill them.
That's not strictly true. Proteas need nutrients just like any other plant, but their are a little more exacting than some. It's not fertiliser that does the damage but high phosphate levels and intense bursts of nutrients that lead to overly rapid growth. Avoid most general garden fertilisers, fresh animal manures and anything with added superphosphate. Because proteas will tolerate poor soils, it is often easier not to feed them rather than risk damage, but you'll certainly get better results if you apply a slow release, low phosphate fertiliser in late winter and mid summer. This will keep the plants growing slowly but steadily; any bolting into growth tends to weaken them.
Myth 2: proteas only grow near the coast.
Not true. Many proteaceous plants come from inland areas. They will tolerate salt breezes but there is no general preference for coastal conditions.
Myth 3: proteas like wind.
That's also not entirely true. Proteaceous plants do not tolerate wet foliage or high humidity for long periods and in areas prone to these conditions extra ventilation will help reduce the incidence of fungal diseases. However, most proteas have brittle branches that snap or split in strong winds so there's no reason to presume that they prefer windy locations.
Myth 4: proteas need a hot sunny position.
Yes, most Proteaceae prefer full sun or something near to it. But that doesn't necessarily mean the hottest, most baked position you can find. Although they will survive severe conditions once established, extreme heat and drought will cause damage, especially to young plants. Shade from the hottest sun will prolong the flower display and, provided the drainage is good, occasional deep watering is also recommended.
Myth 5: proteas are short-lived.

Some are and some aren't. Old plants are normally removed long before the end of their natural lives because they tend to become rather woody and untidy. You can generally reckon on a useful lifetime of at least 8 years for Leucadendron and Leucospermum, and around 12 years for Protea. However, large species, such as Grevillea robusta and Banksia integrifolia, may continue to be effective garden plants for several decades.
Planting
Most proteaceous plants are sold in containers and are ready to plant right away. However, the best planting time depends on your climate. Autumn or winter is best in mild areas as this is when moisture requirements are at their lowest, while spring is the preferred time if regular frosts are expected as this allows the young plants to get well established before having to endure winter conditions.
Start by digging a hole at least twice the size of the plant's container, this large volume of loose soil will encourage good root development.. Additional drainage material can be added to the hole if necessary, otherwise planting is just a matter of removing the plant from its container, loosening any spiralling roots before placing in the hole, then refilling the hole and firming the plant into position. Large specimens will require staking to prevent wind damage.
Cut flower use
Many proteaceous plants make excellent long-lasting cut flowers. Leucadendrons in particular are widely planted solely for the purpose of providing material for floral decorations. Protea, Leucospermum, Banksia and Serruria flowers can all be used to make impressive large arrangements while the less dramatic blooms of Grevillea and Isopogon are better suited to more dainty work.
Some flowers, particularly goblet-shaped Protea flowers dry well although they do tend to disintegrate rather suddenly after a few months. Other genera such as Banksia and Leucadendron produce seed heads or cones that can be used in dried arrangements.
Pruning
Most proteaceous plants need occasional trimming and tidying. This may be to improve their growth habit or to remove old flowers or seed heads that have become dry and unsightly.
How far to cut back is the usual question. This varies with the genera, although as a rule only light pruning is recommended as there is a general reluctance among proteas to reshoot from bare wood. Of the common genera Banksia and Grevillea will withstand hard trimming, as will Leucadendron, Telopea and Mimetes, but pruning of Dryandra, Leucospermum, Serruria, Paranomus and most Protea species should be restricted to a light annual trimming.
The best time to prune is usually immediately after flowering unless you want to leave a few seed heads to mature for use as dried decorations. In areas where there is the possibility of frost damage, it is advisable to leave pruning autumn and winter-flowering plants until spring.
Container Growing
Some proteaceae can make good container plants, but you will have to be careful with your choice of potting mixes and fertilisers. Potting mixes need to be very free draining and often benefit from added coarse material such as shingle chips or pumice. Bark based mixes seem to work well but some growers feel they produce too much ethylene, which may harm the plants in the long run. Many commercial growers use soil based mixes and they generally prefer relatively poor and gritty volcanic soils.
Even plants with low nutrient demands will eventually exhaust their potting mix, so you will have to apply fertiliser occasionally. Use mild liquid fertilisers or special low-phosphate slow release pellets. Provided you are cautious the plants should respond well.
Propagation
Proteas can be frustratingly difficult plants to propagate. Fresh seed often germinates well only for the seedlings to collapse after a few weeks. This is usually due to a fungal disease that blackens the foliage and eventually kills the young seedlings. Regular fungicide applications are important. Prick out the young seedlings into a coarse, free draining, unfertilised potting mix once they have their first true leaves.
Cultivars and selected forms must be propagated vegetatively. The usual method is firm semi-ripe cuttings in late summer and autumn. The success rate varies markedly; some cultivars, such as Leucadendron 'Safari Sunset', strike quite easily while many others may be virtually impossible without professional equipment.
Pests and Diseases
Grown under the right conditions proteaceous plants are relatively free of pests and diseases, or rather they're not attacked by anything out of the ordinary. The most widespread problems are leaf roller caterpillars and scale insects, which can eventually lead to sooty mould.
When growing proteas from seed you will doubtless lose some to the fungal disease mentioned above. This disease, which appears to be a type of damping off, can sometimes also attack more mature plants. It appears to be far worse in excessively wet conditions or after long periods of high humidity. Good ventilation and avoidance of overcrowding are effective preventatives and regular spraying with fungicides may control the problem.
Common genera
Many of these plants are not widely available at garden centres, although specialist growers would consider them to be just the most common genera and are likely to stock others as well. All of the species and genera covered here are evergreen unless otherwise stated.
Aulax
This is a South African genus of small to medium sized shrubs. This genus and Leucadendron are the only dioecious (separate male and female plants) members of the Proteaceae. Seed of all three species, Aulax cancellata, Aulax pallasia and Aulax umbellata, is available but only Aulax cancellata is commonly planted. It grows to 1.5-2m × 1m and has fine needle-like leaves. In spring, female plants produce red edged yellow flowers that develop into red seed cones. The catkin-like male flowers are yellow, as are those of Aulax pallasia and Aulax umbellata, the female flowers of which are not very showy. Aulax pallasia grows to about 3 m and Aulax umbellata about 1.5m. All are hardy to about -5°C and are usually raised from seed.
Banksia
An Australian genus of about 60 species, ranging in size from ground covers to medium-sized trees. The flowering season is primarily from late winter to late spring and most species have cylindrical cone-like flower heads composed of densely packed filamentous styles radiating from a central core. Creamy yellow to light golden-yellow is the predominant colour range, although a few species, such as Banksia ericifolia and Banksia praemorsa, have golden-orange flowers and those of Banksia coccinea are red. Most species have narrow serrated leaves that are mid to deep green above and silvery grey on the undersides but Banksia ericifolia has fine needle-like leaves. Leaf size varies from very small up to the 50cm long leaves of Banksia grandis. Hardiness varies with the species, some are quite frost tender but some will tolerate -10°C.
Relatively few are seen in nurseries but the seed of most species can be obtained from Australia. Banksia ericifolia and Banksia integrifolia are the most widely grown and are also the hardiest of the common species, both withstanding -10°C once well established. There are hardly any cultivars or selected forms of Banksia in cultivation. Species may be raised from seed and most will also strike quite freely from semi-ripe cuttings.
Dryandra
An Australian genus of around 60 species of shrubs ranging in height from about 1-4 m. Most have narrow, mid to deep green leaves that are often very long and narrow with sharply toothed edges. The rounded flower heads, which appear from mid winter, are usually light to bright yellow. The most common species is Dryandra formosa, which grows to about 3m and is hardy to around -5°C once established (most of the other species are less hardy). Dryandras are superb long-lasting cut flowers and some will also dry well. They will grow on extremely poor soil and generally react badly to most fertilisers. Raise from seed or semi-ripe cuttings, which are often difficult to strike.
Embothrium
The Chilean Fire Bush (Embothrium coccineum) is a small tree around 5m × 2.5m. It has 100mm long, leathery, bright green leaves that may become somewhat sparse on older plants. In mid to late spring the tree turns vivid orange-red as the honeysuckle-like tubular flowers open - the flowering season is brief but spectacular. Two forms are grown: 'Longifolium' and 'Lanceolatum'; 'Longifolium' is the more common cultivar. It is a vigorous upright plant that is quite drought tolerant and hardy to about -10°C. 'Lanceolatum' is a stockier grower with narrow leaves. It demands more moisture but withstands harder frosts, up to -15°C with some protection. However, in very cold winters it may lose up to two thirds of its foliage. Overall Embothrium requires more moisture than most Proteaceae but good drainage is still important. It may be grown from seed but is usually propagated by semi-ripe cuttings.
Grevillea
With some 250 species, this is the largest of the Australian proteaceous genera. Most of the common garden species and cultivars are ground covers to medium-sized shrubs (up to 3m) with needle-like foliage. However, some species are far larger. The silky oak (Grevillea robusta), which is often seen in mild area, can grow to 20m and in common with most of the larger species it has large pinnate leaves. Grevillea banksii has similar foliage but only grows to about 3.5m × 3m.
The more densely foliaged plants, especially Grevillea juniperina and Grevillea rosmarinifolia, are often used as hedging plants. These plants grow to at least 1.5m high.
Grevillea flowers are often describe as 'spider flowers'. This refers to the styles of some species, which tend to radiate from the centre like a spider's legs. Some species have 'toothbrush' flowers; the styles are all on one side like the bristles of a toothbrush. The best known example of this type of flower is the common red-flowered cultivar 'Robin Hood'.
Many Grevillea cultivars are cultivated and they generally adapt well to garden conditions. Among the more popular are 'Jenkinsii' (a heavy flowering form of the red-flowered Grevillea rosmarinifolia), 'Robyn Gordon' (orange-red to red toothbrush flowers) ×gaudichaudii (deep red), 'Austraflora Canterbury Gold' (light golden yellow) and many of the Poorinda cultivars. Grevilleas are among the more widely available proteaceous plants and most nurseries stock a good selection.
The species and hybrids vary enormously in hardiness. Some will stand little or no frost but others, such as Grevillea rosmarinifolia, will tolerate frosts of -10°C or lower; all prefer full sun with good drainage. The species are easily raised from seed and most hybrids strike quite freely from semi-ripe cuttings taken in late summer or autumn.
Hakea
This Australian genus includes about 130 species, few of which are widely cultivated. The most common is probably Hakea laurina, the Pincushion Hakea. When not in flower, this species could easily be mistaken for a small eucalyptus. It has bluish-green narrow, oblong to sickle-shaped leaves and reddish-brown bark. It grows to about 6m × 4m and mature trees have a slightly weeping habit. The name pincushion refers to the flowers, which are spherical, with numerous radiating styles. They appear in late autumn and early winter, opening cream and turning to orange and red as they age. This shrub is hardy to about -5°C once well established and is easily grown in most well-drained soils.
Of the other species, the most common are Hakea salicifolia, Hakea prostrata and Hakea sericea. They are hardy to about -8°C or slightly lower and are easily grown in most soils. Hakea salicifolia has narrow, willow-like leaves, spidery, white flowers that are produced in spring. It grows up to 5m high and will tolerate poor drainage. Hakea prostrata and Hakea sericea have fine needle-like leaves and white or pale pink flowers in winter and early spring. It grows to about 3m × 2m. All member of this genus are usually raised from seed but some can be grown from cuttings. A few, such as H. franciscana, are weak growers that often perform better when grafted onto more vigorous stocks, such as Hakea salicifolia.
Isopogon
Drumsticks, which refers to the shape of the flower stems and unopened buds, is a name often used for Isopogon anemonifolius but it can also be applied to the genus as a whole. It is an Australian genus of 34 species of small to medium sized shrubs, most of which grow from 1-2m high and about as wide. They have a preference for poor but well-drained soil and will quickly collapse if over-watered or overfed. Most species have narrow lanceolate leaves about 75mm long and some, such as the common Isopogon anemonifolius, have finely cut foliage reminiscent of Marguerite daisy or Anemone leaves.
The flower heads, which open in spring and early summer, are composed of a central cone from which radiate numerous styles. Some species have short stiff styles but in others they are long and filamentous. The flower colours are mainly white, yellow or pink. The two most widely grown species, Isopogon anemonifolius and Isopogon anethifolius are hardy to about -5°C, but many species, such as Isopogon cuneatus and the temptingly beautiful pink and yellow-flowered Isopogon latifolius, are damaged at temperatures below -2°C. Isopogon species are usually raised from seed.
Knightia
The Rewa Rewa or New Zealand Honeysuckle (Knightia excelsa) is the best known of the two New Zealand proteaceous species. In the wild it can grow to be a tall narrow tree up to 25m high and it is one of the few proteaceous plants to have been harvested for its timber, which is very attractively marked. In gardens it is more restrained and seldom exceeds 8m × 3.5m. Rewa rewa has semi-glossy, deep green to bronze-green, narrow, lanceolate to oblong leaves that are very tough and leathery. In summer it produces tubular honeysuckle-like flowers that develop from buds covered in a reddish brown tomentum. As the flowers open the tomentum covered sepals and the petals curl back to form a congested mass in the centre of the flower head. The flowers, which can smell unpleasant, are followed by conspicuous brown, velvety seed pods. Rewa Rewa is easily grown in moist well-drained soil in sun or partial shade and is hardy to about -5°C or slightly lower once established. It may be grown in any coastal area if protected when young. New Zealand honeysuckle is usually raised from seed and garden centres often stock ready-grown plants.
Leucadendron
Species of this genus are the most widely grown of the South African Proteaceae and many are valued for the long-lasting qualities of their flower bracts once cut. Most are medium-sized shrubs around 1-2.5m high. However, one of the best known species, the silver tree (Leucadendron argenteum), can grow to 10m high and the less widely grown Leucadendron eucalyptifolium may reach 5m.
Many species and cultivars are grown, but probably the most widely planted is 'Safari Sunset'. It is a hybrid between Leucadendron laureolum and Leucadendron salignum and is fairly typical of the genus. It has narrow, lanceolate leaves that are up to 100mm long. Some species, such as L. argenteum, have tomentose foliage but 'Safari Sunset' does not. The upward-facing foliage densely covers the narrow, upright branches and develops deep red tints at the flowering tips. Deep red leaf bracts enclose the flower cones. As the insignificant flowers near maturity, the bracts become intensely coloured. 'Safari Sunset' has red bracts but others develop cream, yellow, pink or orange tones. 'Wilson's Wonder' (yellow and orange-red), 'Maui Sunset' (cream, yellow and red) and 'Rewa Gold' (yellow) are among the most spectacular. Leucadendrons generally develop their best colours from mid to late winter but 'Jester' a pink, cream and green variegated sport of 'Safari Sunset' is brightly coloured throughout the year.
The species and hybrids vary considerably in hardiness but most will tolerate frosts of at least -3°C provided they have good drainage and the humidity is not excessive. 'Safari Sunset' is hardy to about -8°C and most of the numerous Leucadendron salignum and Leucadendron laureolum hybrids are nearly as hardy. In the North Island leucadendrons generally thrive in all but the coldest central areas and they can be grown with varying degrees of success in all coastal areas of the South Island.
Leucadendrons can be tricky to propagate. Reasonably firm cuttings taken in early autumn are usually the easiest to strike but gardeners without specialised propagating facilities may experience problems and although seed germinates well, it is inclined to damp off. Garden centres often stock a good range of plants.
Leucospermum
A South African genus of about 50 species, most of which are medium to large shrubs that grow to about 1.5-3m high. Some, such as Leucospermum reflexum, have strongly upright growth habits but most, including the commonly cultivated species, Leucospermum cordifolium, are dense and bushy. Both of these species have tomentose greyish-green leaves that are usually broadly oval shaped, often with small red-tipped lobes. The leaves of Leucospermum reflexum are narrower and greyer than those of Leucospermum cordifolium. Leucospermum reflexum can grow to 3m × 3m but Leucospermum cordifolium is usually around 1.5m × 1.5m.
The flowers are variously described as Catherine wheels, pincushions and sky rockets, all of which refer to the numerous radiating styles. These are often incurved, creating a cupped effect. The flower heads of Leucospermum cordifolium are quite globular while those of Leucospermum reflexum have drooping styles at the base of the flower. The flowers usually appear in late spring and continue for about two months. They are attractive when fresh but often become unsightly once they die off.
Most garden leucospermums are cultivars of Leucospermum cordifolium and are hardy to occasional frosts of about -5°C, but they resent wet or humid winter conditions, which can often lead to tip die back. Good drainage is also very important. Cuttings taken in early autumn are the most likely to strike but without proper equipment they may prove difficult and seed often germinates well only to be killed by fungal diseases. Gritty well-drained soil, regular fungicide use and just enough water to keep the seedlings standing up are the keys to success. The orange-flowered 'Harry Chittick' is the plant most commonly stocked by nurseries and it is one that performs very well.
Mimetes
This South African genus includes 11 species, only one of which is widely grown. Mimetes cucullatus has 40mm long oblong leaves with small lobes at the tips, that densely cover the branches like upward facing scales. The small white flowers are enclosed within leaf bracts that change colour to a bright red as the flower buds mature. Mimetes may flower throughout the year but is usually at its best in late spring when the new growth appears, as this is also red. Mimetes cucullatus grows to about 1.5m × 1.5m and is hardy to around -3°C. It prefers moist, well-drained soil and is not very drought tolerant. This species is usually raised from seed.
Paranomus
The most common species of this 18-species genus, Paranomus reflexus, is an undemanding 1.5m × 1.8m bush with bright yellow bottle-brush-like flower heads in winter and spring. The foliage is anemone-like and very finely cut; the flower stems have small diamond shaped leaves just below the flower heads. It is easily grown in any well-drained soil in full sun. Although the plant is hardy to about -5°C, the flowers are damaged by frosts over -2°C. It is usually raised from seed.
Persoonia
An Australian genus of around 75 species of shrubs, mostly under 2 m tall and some quite small. Known as geebungs, by far the best-known species is the Pine-leaf Geebung (Persoonia pinifolia), an eastern Australian native that is one of the larger species, capable of reaching 3 m tall. It has a weeping habit, fine needle-like leaves and small yellow flowers. Most geebungs will tolerate about 2 to 5°C of frost.
Protea
Protea is a genus of about 80 species that is confined to southern Africa and concentrated around the Cape of Good Hope. The species range in size from less than 50cm high to over 4m. Most commonly grown proteas are small to medium sized shrubs in the 1-2.5m high range.
The best known species is Protea neriifolia. It has narrow leaves up to 150mm long that are covered with a fine tomentum when young. In autumn, winter and spring, upright, 125mm long × 75mm wide goblet-shaped flowers are carried at the tips of the branches. They are composed of a woolly central cone surrounded by overlapping, upward-facing, petal-like, deep reddish-pink bracts tipped with a fringe of black hairs. Many forms with varying colours of bract and tip hairs are grown. Several other species, such as Protea magnifica and Protea laurifolia, have similar flowers.
The central cone, often with many incurving styles, is common to all Protea species but the arrangement of the bracts varies. Many have them arranged in a stellate or star-shaped fashion. The King Protea (Protea cynaroides) is the best known of this type. Its flowers can be up to 300mm in diameter. The flowers of the king protea face upwards but others, such as greenish-yellow-flowered Protea sulphurea, have downward facing flowers.
The foliage is also variable. It may be needle-like, as in Protea nana, lanceolate, oblong or rounded. It can be silvery grey, glaucous or bright green depending on the species and it may or may not be tomentose.
Likewise, hardiness varies considerably. Most species will tolerate at least -3°C with good drainage and low humidity but many are considerably tougher. Protea neriifolia will withstand -5°C and Protea grandiceps will often survive -10°C when well established. Proteas do well over most of the North Island and many species can be grown as far south as Christchurch with a little winter protection.
Protea species are often raised from seed, which germinates well, but the seedlings may be difficult to keep alive. Hybrids and cultivars must be propagated vegetatively. The usual method is firm semi-ripe cuttings taken in late summer and autumn. Specialist growers stock many species and cultivars while garden centres seldom have anything other than the most common plants.
Serruria
Blushing Bride (Serruria florida) is very popular with florists because its Nigella-like papery white bracts are very delicate and last well as cut flowers. The bracts, which are surrounded with finely cut lacy leaves, are produced freely in winter and spring. Blushing Bride can be difficult to grow, because not only is it frost tender (it tolerates only occasional exposure to -2°C), it must also have full sun and absolutely perfect drainage. It is one of a genus of 44 species from South Africa, of which the only other species commonly grown is Serruria rosea. It is a densely foliaged 70cm × 90cm bush with small pink bracts and is slightly hardier and definitely easier to grow than Serruria florida. Serruria species should be raised from seed.
Stenocarpus
The Queensland Firewheel Tree (Stenocarpus sinuata) is a large tree (12m × 8m) that produces a magnificent display of orange to red flowers in summer. It has large, glossy, dark green leaves that are deeply lobed. The flowers are tubular and are carried in flattened clusters that radiate spoke-like from a central hub, hence the name firewheel tree. It is hardy to about -4°C once well established but is very tender when young and does best in moist well-drained soil in full sun. Stenocarpus salignus is a species with long, narrow leaves and cream flowers. It is smaller and hardier than Stenocarpus sinuata. Stenocarpus is usually raised from seed.
Telopea
Natives of Australia, the waratah genus includes just four species. The New South Wales waratah (Telopea speciosissima), which is the one most commonly grown has oblong, finely serrated leaves that are up to 125mm long with small notches or lobes at the tips. It develops into a large shrub or small tree up to 5m × 5m. The flowers, which are produced in spring and carried at the tips of the branches, are impressively large, bright red, and composed of numerous incurving styles surrounded by red foliage bracts. Several cultivars, such as the semi-dwarf 'Forest Fire' (2m × 2m) are reasonably commonly available. The 'Victorian Waratah' (Telopea oreades) is a similar plant with slightly lighter coloured leaves and flowers. Both of these species and the cultivars are hardy to around -8°C.
Waratahs prefer moist well-drained soil in full sun and once established they require little care. But many die during the initial establishment period. This is possibly due to essential mycorrhiza failing to establish. These minute fungi form a symbiotic relationship with the plants' roots and are vital in the uptake of nutrients. It has been suggested that taking soil from around an established waratah and putting it around new plants may help lessen these establishment difficulties. Waratahs may be raised from seed or semi-ripe cuttings but they are difficult to raise. Some success has been achieved with tissue culture and this is how some of the new cultivars are produced.
Toronia
The sole species in this genus is the lesser known of the two New Zealand proteaceous species. Formerly listed as Persoonia toru, it is now known as Toronia toru. A small bushy tree that can grow to about 9m × 5m, it is usually far smaller in gardens. The narrow, lanceolate olive green to bronze leaves are about 100mm long but may grow to over 150mm on mature trees in sheltered sites. The buff coloured starry flowers, which appear in late winter and early spring, are carried in racemes and develop from golden brown felted buds. It is easily grown in any moist well-drained soil in full sun or partial shade and is hardy to about -8°C once established. Toronia toru is a relatively unspectacular plant but its flowers are pleasantly honey-scented and it is interesting because it is one of our more unusual natives. This species may be grown from cuttings, but as they are usually difficult to strike, seed is the preferred method.


The Protea Family (Proteaceae)

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