Growing Grevilleas

Course CodeVHT118
Fee CodeS2
Duration (approx)100 hours
QualificationStatement of Attainment

Learn to Grow Grevilleas​

  • As a landscape plant
  • As a cut flower
  • As a container plant

There are more than 250 species of Grevillea and hundreds if not thousands of different varieties and hybrids, many probably not yet named.

  • About 50% of all Grevilleas are tropical.
  • The majority of species are stenobasic (ie. having more or less one dominant stem or trunk).
  • Twenty of the known species are trees.
  • 176 of the known species are shrubs
  • 17 of the known species are prostrate shrubs

 

 

Lesson Structure

There are 8 lessons in this course:

  1. Introduction.
    • Scope and Nature of the Grevillea genus
    • Review of the system of plant identification
    • Botanical Terminology used to describe Grevilleas
    • Flower Structure
    • Plant Name Pronunciation
    • Characteristics of the Proteaceae family
    • Characteristics of the Grevillea genus
    • Different ways of classifying Grevilleas into groups: by flower type (eg. toothbrush); McGilveray's system dividing into 11 groups
    • Resources, information contacts (ie: nurseries, seed, clubs etc.)
  2. Culture
    • Environment, Nutrition, Soil Requirements
    • Planting, staking, mulching
    • Water management
    • Pest and disease found on Grevilleas
    • Feeding, pruning, protection from wind, salt air, etc.
  3. Propagation
    • Methods of propagating Grevilleas
    • Cutting Propagation
    • Methods to Improve Cutting Success
    • Seed Propagation of Grevilleas
    • Transplanting
    • Hardening off and Growing on Young Plants
    • Grafting Grevilleas
    • Tissue Culture and Aerial Layering
  4. The Most Commonly Grown Varieties.
    • Clearview Hybrids
    • Grevillea banksii and banksii hybrids
    • Grevillea alpina
    • G. rosmarinifolia
    • G. dimorpha
    • G. lavandulaceae
  5. Other Important Groups.
    • G. alpina cultivars and hybrids
    • G. rosmarinifolia cultivars
    • G. Poorinda hybrids
  6. Other Grevillea Varieties.
    • Ground Cover Grevilleas
    • Trees
    • Review of many other species
  7. Making The Best Use of Grevilleas
    • Cut Flowers
    • Bird Attracting
    • Scented Grevilleas
    • Container Growing Grevilleas
    • Potting and Types of containers
    • Growing Grevilleas in Baskets
    • Rock Gardens
    • Designing a Garden with Grevilleas; design principles, garden styles, drawing a plan
  8. Special Assignment: On one selected plant or group.
    • Problem Based Learning Project
    • Plan the establishment of a collection of different cultivars of Grevilleas suited to growing in a specified locality.

Each lesson culminates in an assignment which is submitted to the school, marked by the school's tutors and returned to you with any relevant suggestions, comments, and if necessary, extra reading.

Aims

  • Identify a range of different Grevilleas.
  • Explain the culture of different types of Grevilleas.
  • Propagate different Grevilleas
  • Discuss different uses for Grevilleas
  • Compare identifiable characteristics and cultural preferences of a range of Grevilleas.
  • Discuss a range of Grevillea hybrids and cultivars
  • Identify and compare a range of commonly cultivated Grevilleas.
  • Discuss one Grevillea species, cultivar or type in depth.

OVER 250 SPECIES

Grevilleas are a group of around 250 or more species of plants (genus); all but seven species coming from.

They are widespread across, occurring in both cool temperate, and hot tropical climates. There are species that grow satisfactorily in most parts of the world.

Known commonly as “Spider Flowers”; the Grevillea flower is more like a brush than a traditional flower. It has obscure petals, but is none the less very colourful. Flower colour varies greatly; and most hold their flowers for a long period.

 

Grevilleas include both small to very large plants (from prostrate ground covers, through small and medium shrubs up to large trees).  Their hardiness is variable according to species. The foliage is also variable ranging from small, entire leaves to lobed or pinnate leaves. All are arranged alternately on the stems and some have hairy under surfaces.  Most have a  medium to fast growth rate.

 

The way you should treat a particular species of Grevillea will differ from place to place, and according to what you are trying to get from the plant.
 
 
 
Grevillea rosmarinifolia

Grevillea oleoides

 

General Guidelines for Grevillea Growing

  • Good drainage is perhaps the most important factor -soils can be sands or clays for many species, provided they are drained. Some species will tolerate water logging for perhaps a week or two, but these are exceptions rather than the rule.
  • Grevilleas are shallow rooted plants – mulch is beneficial to protect the roots from exposure and to retain moisture in the soil.
  • Due to their shallow rooting - it is beneficial to stake Grevilleas that are growing in raised beds.
  • Grevilleas may be root-pruned (unlike many other native) – you can remove up to 1/3rd the root ball of pot bound specimens however it is advisable to use a rooting hormone to promote root growth afterwards.
  • Grevilleas cannot be moved once they are established – very young plants can be moved in autumn to early spring - but will need extra attention to watering for some time after. Rooting hormones may be of benefit.
  • Use only low phosphorus fertilisers.
  • Select species to suit the environment in which they are to grow.
  • Never buy pot-bound or sickly looking plants.
  • Grevilleas will grow in pots but are best planted out before they reach 3 years old.
  • Attract birds to your garden to aid in pollination – you may just produce a new variety!
  • Never plant Grevilleas in heavy shade.
 
Grevilleas were Introduced to the UK in the late 1700's
By the early 1800's Grevilleas were being grown successfully in at least some English gardens. 
 
Grevilleas are both trees, shrubs and ground covers. Almost all are indigenous to Australia with a few from surrounding areas (occurring in Papua New Guinea, Indonesia (Celebes) and New Caledonia).
 
The first grevilleas were collected on Cook’s voyage to Australia in 1770, and initially and unofficially given the genus name “Leucadendroides” because of it’s similarity to Leucadendron. Early botanists then listed grevilleas as belonging to the genus, “Embothrium”.
 
Eventually the name “Grevillea” was established, after Charles Francis Greville, a British member of parliament, and one of the founders of the Royal Horticultural Society in the UK.
 
There are 248 species according to D. J. McGillvray, 1993. Other experts vary in the number of species; some suggesting many more. Roger Elliott and David Jones suggested 251 species in their 1990 edition of “Encyclopaedia of Australian Plants”. Wrigley and Fagg (in “Banksias, Waratahs and Grevilleas (1988) recognise the fact that many growers still use names that might not be used by botanists; and as such, recognise 273 species.
 
 
WHERE MIGHT THIS COURSE LEAD?

 Whether you are simply a passionate hobbyist or someone who works in horticulture; you cannot go wrong undertaking this course.

Very few people ever study grevilleas to the depth that this course can take them; but by exploring and learning a lot more about this genus of plants you will be setting yourself apart from other gardeners and professional horticulturists. Grevilleas are a plant with huge untapped potential. Just as roses, azaleas and fuchsias became "fashionable plants to develop and proliferate in the past; Grevileas are similarly seeing a surge in popularity not just in the countries they come from, but world wide.

With the learning you achieve throughout this course, your awareness of the scope, nature, and potential of Gravilleas, will grow.

This is a course for all sorts of people:

  • Gardeners
  • Landscapers
  • Cut-flower growers
  • Bush or natural garden designers
  • Environmentalists
  • Plant Breeders
  • Garden writers and teachers
  • and others
 

HOW TO ENROL

 

 Click box below on left hand side -follow instructions.

 

 

IF YOU NEED ADVICE - click here to use our FREE ADVISORY SERVICE

 
 
 

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