The protea family
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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 proteas. 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 particular genus) 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 mild, fairly dry areas and often thrive near the coast. Inland, unseasonable early and late frosts can 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. See the pests and diseases chapter for the details of identification and
control.
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, A. cancellata, A. pallasia and A. umbellata, is available but only A. cancellata is commonly sold
ready-grown in garden centres. It grows to 1.5–2 m × 1 m 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 A. pallasia and A. umbellata, the female flowers of
which are not very showy. A. pallasia
grows to about 3 m and A. umbellata
about 1.5 m. 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 B. ericifolia and B. praemorsa, have golden-orange flowers and those of B. coccinea are red. Most species have narrow serrated leaves that are mid to deep green above and silvery grey on the undersides but B. ericifolia has fine needle-like leaves. Leaf size varies from very small up to the 50 cm long leaves of B. grandis. Hardiness varies with the species, some are quite frost tender but some will tolerate -10°C.
Relatively few are cultivated outside their homeland but the seed of most species can be obtained from Australia. B. ericifolia and B. 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 D. formosa, which grows to about 3 m 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 (E. coccineum) is a small tree around
5 m × 2.5 m. It has 100 mm 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 3 m) with
needle-like foliage. However, some species are far larger. The silky oak (G. robusta), which is often seen in mild
area, can grow to 20 m and in common with most of the larger species it
has large pinnate leaves. G. banksii
has similar foliage but only grows to about 3.5 m × 3 m.
The more densely foliaged plants,
especially G. juniperina and G. rosmarinifolia, are often used as
hedging plants. These plants grow to at least 1.5 m 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 grown in gardens and they generally adapt well to most conditions. Among the more popular are ‘Jenkinsii’ (a heavy flowering form of the red-flowered G. 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 G. 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 H. 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 6 m × 4 m 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
H. salicifolia and H. sericea. Both are hardy to about -8°C
or slightly lower and are easily grown in most soils. H. salicifolia
has narrow, willow-like leaves, spidery, white flowers that are produced in
spring. It grows up to 5 m high and will tolerate poor drainage. H. sericea has fine needle-like leaves
and white or pale pink flowers in winter and early spring. It grows to about
3 m × 2 m. 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 H.
salicifolia.
Isopogon
Drumsticks, which refers to the shape of the flower stems and unopened buds,
is a name often used for I. 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 1–2 m 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 75 mm long and some, such as the common I 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, I. anemonifolius and
I. anethifolius are hardy to about
-5°C, but many species, such as I cuneatus
and the temptingly beautiful pink and yellow-flowered I. latifolius, are damaged at temperatures below -2°C. Isopogon species are usually raised from
seed.
Knightia
In the wild the Rewa Rewa or New Zealand honeysuckle (K. excelsa) can grow to be a tall narrow tree up to 25 m 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 8 m × 3.5 m. 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 1–2.5 m high. However, one of the best known species, the silver tree (L. argenteum), can grow to 10 m high and the less widely grown L. eucalyptifolium may reach 5 m.
Many species and cultivars are grown here, but probably the most widely planted is ‘Safari Sunset’. It is a hybrid between L. laureolum and L. salignum and is fairly typical of the genus. It has narrow, lanceolate leaves that are up to 100 mm 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 L. salignum and L. 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
1.5–3 m high. Some, such as L.
reflexum, have strongly upright growth habits but most, including the
commonly cultivated species, L.
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 L.
reflexum are narrower and greyer than those of L. cordifolium. L. reflexum
can grow to 3 m × 3 m but L.
cordifolium is usually around 1.5 m × 1.5 m.
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 L. cordifolium
are quite globular while those of L.
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 L. 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.
Macadamia see Fruit and Nuts chapter
Mimetes
This South African genus includes 11 species, only one of which is widely grown. M. cucullatus has 40 mm 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. M. cucullatus grows to about 1.5 m × 1.5 m 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, P. reflexus, is an undemanding 1.5 m × 1.8 m 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.
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 50 cm high to over 4 m. Most commonly grown proteas are small to medium sized shrubs in the 1–2.5 m high range.
The best known species is P. neriifolia. It has narrow leaves up
to 150 mm long that are covered with a fine tomentum when young. In
autumn, winter and spring, upright, 125 mm long × 75 mm 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 P. magnifica and P. 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 (P.
cynaroides) is the best known of this type. Its flowers can be up to
300 mm in diameter. The flowers of the king protea face upwards but
others, such as greenish-yellow-flowered P.
sulphurea, have downward facing flowers.
The foliage is also variable. It may be needle-like, as in P. 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. P.
neriifolia will withstand -5°C and P.
grandiceps will often survive -10°C when well established. Proteas do well
over most of the 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 (S. 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 S. rosea. It is a densely foliaged
70 cm × 90 cm bush with small pink bracts and is slightly hardier and
definitely easier to grow than S. florida. Serruria species should
be raised from seed.
Stenocarpus
The Queensland Firewheel Tree (S. sinuata) is a large tree (12 m × 8 m) 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. S. salignus is a species with long, narrow leaves and cream flowers. It is smaller and hardier than S. sinuata. Stenocarpus is usually raised from seed.
Telopea
Natives of Australia,
the waratah genus includes just four species. The New South Wales waratah (T. speciosissima), which is the one most
commonly grown has oblong, finely serrated leaves that are up to 125 mm long
with small notches or lobes at the tips. It develops into a large shrub or
small tree up to 5 m × 5 m. 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’
(2 m × 2 m) are reasonably commonly available. The ‘Victorian
Waratah’ (T. 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 our two native proteaceous species. Formerly listed as Persoonia toru, it is now known as Toronia toru. A small bushy tree that
can grow to about 9 m × 5 m, it is usually far smaller in gardens.
The narrow, lanceolate olive green to bronze leaves are about 100 mm long
but may grow to over 150 mm 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.
Copyright Geoff Bryant
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