This book focuses mostly on Proteas, but also considers some of the other Proteaceae genera that are more widely cultivated.

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1 CHAPTER 1: INTRODUCING THE PROTEA FAMILY There are around 1700 species and 79 genera of plants in the Proteaceae (Protea) family, and most are indigenous to the southern hemisphere. Around half of these species come from Australia and a quarter from southern Africa. Protea is internationally, one of the best-known and most widely grown genera from the Proteaceae family. Proteas originate in southern Africa and many species are known and grown for their large colourful flower heads. This book focuses mostly on Proteas, but also considers some of the other Proteaceae genera that are more widely cultivated. History & Distribution The name Protea was first published in 1735 by the famous botanist Carl Linnaeus who referred to the genus now known as Leucadendron. Linnaeus was impressed by the diversity of these plants and named them after the Greek sea god Proteus who was believed to be able to change his form at will. The Proteaceae family includes many prized garden plants. South African Proteaceae plants are mostly from the Cape Province region, but also come from north to central Africa extending to tropical areas. The genus Protea consists of around 100 species of shrubs and small trees. Other regions of the southern hemisphere where Proteaceae plants may be found include Central and South America which have about 90 species. The New Guinea islands have about 45 species. A smaller number of species are found in South East Asia, New Caledonia and New Zealand, and mainland New Guinea. Many Australian native genera belong to the Proteaceae family including: Grevillea, Hakea, Banksia, Dryandra, Stenocarpus, Dryandra, Isopogon, Persoonia, Conospermum, Franklandia, and Petrophile. Closely related South African genera are often included when people talk loosely about the Protea, including Leucospermum and Leucadendron. These are commonly grown alongside Proteas by nurseries which specialise in growing Proteas, or Protea cut-flower growers, due to their similar cultural requirements. However, strictly speaking they are not Proteas. page 6

2 leucospermum cordifolium page 7

3 Characteristics Most Proteaceae family members share the following characteristics: Flowers are tetramerous (i.e. made up of four similar parts or segments). What usually appears to be a single flower is actually a combination of many small flowers clustered together to create a flower head. There are therefore individual flowers within each flower head. Individual flowers typically have the following components: 1. Four tepals these are outer segments of a flower that may appear like a petal but in reality cannot be distinguished between being either a petal or sepal. 2. The tepals are enclosed in a valvate bud (valvate is where the edges of the scales enclosing the bud are butting up to each other without overlapping). 3. Four basifixed stamens. 4. A single carpel (i.e. female structure) in each flower. In some species, male and female parts can be on separate plants. Leaves are thick and leathery - this type of foliage allows them to withstand water stress better than many other types of plants. They are likely to be wind-resistant and tolerant of dry air conditions (i.e. low humidity). Leaf shape can vary from genus to genus but leaves are normally arranged alternately (rarely opposite) or scattered on the stem. Most grow continuously all year round in mild climates (some have a short dormant period over summer). Most have proteoid roots (these are a type of root which is able to absorb nutrients from soils which have very low levels of nutrients where other types of roots would not be able to absorb nutrients). Proteaceae plants will grow on relatively infertile soils, and in fact some do not tolerate fertile soils. There tends to be a great deal of variation within a species in terms of the appearance of the flower, foliage and growth habit. Proteaceae plants include ground cover plants, through to small and large shrubs and tall trees. Molecular analysis shows that Proteaceae is closely related to the family Platanaceae (Plane Trees). Naming of Proteaceae Plants Occasionally, you may discover that the same plant appears to have two different scientific names. If there is a good argument for both being valid, whether in the past or present, the two names may be considered to be synonyms (i.e. they are interchangeable because they refer to the same plant species). A plant synonym may sometimes be written using the abbreviation syn. in brackets after the plant name e.g. Protea aurea (syn. P. longifolia). page 8

4 There are a number of official bodies, each with arguable credibility, that control the naming of Proteaceae species and, in some cases, other plants. These various bodies may authorise new names when a new species or cultivar is encountered and, sometimes, they may authorise a change in an existing plant name. These bodies do largely agree with each other, but not always. You may sometimes encounter what appears to be a conflict in plant naming within literature that was written in the past or which was written by plant experts who are not fully up to date with taxonomic changes. Conflicts may also arise where one plant naming authority opposes a name alteration that is accepted by another. These various authorities include: The International Proteaceae Register and Checklist - a body that operates out of South Africa and which deals with all Proteaceae plants that are not indigenous to Australia. The Australian Cultivar Registration Authority - an Australian based body dealing with all plants indigenous to Australia, including Proteaceae. The International Botanical Congress (IBC) - manages the naming of plants amongst botanists around the world. The International Horticultural Congress - manages the naming of plants amongst horticulturists internationally, and sometimes comes into conflict with the IBC. Herbariums are centres where plant naming is managed. These are often attached to botanic gardens and tend to operate with authority from their government to manage plant naming in that jurisdiction. Major horticultural bodies such as the Royal Horticultural Society in the UK, or nursery industry associations, also have a great deal of influence upon what plant names are used and promoted within their area of influence. Sometimes these bodies might not adopt changes to plant names made by academics. Despite the apparent potential for confusion in the world of plant names there is, in reality, a great deal of agreement amongst the majority of these authorities most of the time. It is however important to appreciate that there can be, and always will be, occasional conflicts in naming plants. If you are able to appreciate these difficulties, then it ought to mean that one should never be too pedantic about the subject. Culture There are a range of things that are generally common to Proteaceae plants. These include: Most need good drainage and can be susceptible to poor drainage. Many are good as cut flowers. Many have a lot of nectar produced in the flowers; which in turn makes them attractive to birds, insects and some other wildlife. page 9

5 Many can be pruned relatively hard, and if healthy will grow back strongly. In appropriate conditions, most Proteaceae will live well beyond fifteen years - some, although only a minority, will live beyond 100 years. Many will grow well without a high level of soil fertility - but there are exceptions. Most will propagate from seed - many will also propagate from cuttings. Protea Christine Protea CV Bushfire page 10