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.