Plant Health Short Course

Course CodeSGH5
Fee CodeSG
Duration (approx)20 hours
QualificationCertificate of Completion

Learn to examine a sick plant and systematically determine the type of problem that is affecting it.

  • Self Paced Online Study
  • Help Desk manned by experienced, university qualified horticulturists
  • A skill that many who work in horticulture just don't have


Lesson Structure

There are 6 lessons in this course:

  1. Identifying problems
    • Understanding what can go wrong with your plants
    • More than one problem
    • Finding out what the problem is
    • Conducting an inspection
    • Alternative approach
    • Still unsure?
    • Telltale symptoms
    • The main types of problems
    • Pests
    • Diseases
    • Shortcuts to problem identification
    • What insect is it?
    • Diagnosis of plant disorders
    • Difficult to diagnose problems
  2. Treating problems
    • Different ways to control pests and diseases
    • Cultural control
    • Biological control
    • Physical controls
    • Chemical
    • Legal control
  3. Problems and the plants they affect
    • Flowers & bulbs
    • Fruit & vegetables
    • Indoor, shade & greenhouse plants
    • Shrubs & climbers
    • Trees
    • Lawns
    • Australian natives
  4. Pests
    • The major types of pests
    • Common garden pests
    • Millipedes
    • Wasps
  5. Diseases
    • Disease considerations
    • Types of pathogens
    • Symptoms
    • Understanding diseases
    • Stages in the development of a disease
    • Common diseases
  6. Environmental problems
    • Common environmental problems
    • Foliage burn
    • Pollution
    • Lack of water
    • Drainage problems
    • Frost
    • Hail
    • Shade
    • Temperature
    • Wind
    • Plant tolerance levels
    • Ways to protect plants
    • Protective structures
    • Staking
    • Tree guards
    • Wind breaks
    • Mulching
    • Environmental problems in lawns
    • Appendices
    • Spray programs
    • Stages of growth
    • Simple conversions


Identifying pest and disease problems begins by understanding the categories and sub categories of what can cause illness in a plant. Next you need to become familiar with the signs that suggest which category or sub category you are looking at.

As your familiarity with pest and disease grows through this course and beyond, so does your ability to categorise the problems you are looking at.

Plants can suffer from a range of problems. The types of problems they encounter can include:

PESTS: Included here are animals of various sizes and forms (from microscopic worms to birds, dogs, cows & humans). Insects are the most significant group which can cause damage to plants.

DISEASES: These are problems caused by living organisms other than animals. Fungi, bacteria and viruses are the most common. Not all fungi and bacteria cause problems for plants. In fact, many are extremely important in maintaining the healthy growth of most types of plants.

ENVIRONMENTAL DISORDERS: Problems can caused by environmental factors including things like; poor soil conditions, pollutants, adverse weather conditions such as frosts, strong winds, extremes of temperature, and hail.

NUTRITIONAL PROBLEMS: Too few nutrients can lead to deficiencies, and too many nutrients can cause toxicity in plants. Plants can also suffer from deficiencies when nutrients present in the growing media are not in a form that can be easily used by the plant.

WEEDS: These are plants growing where you don't want them. It is the location of a plant which makes it a weed, NOT the species of the plant. A plant can be weed in one position and a desired plant in another. A weed can be a host plant for pests & diseases or it may compete with your desired plants for nutrients, water, light and space making it  difficult, or even impossible, for your desired plants to maintain healthy growth.            


Often your plants can suffer from more than one problem at the same time. Frequently these different problems are interrelated, with one problem causing the others to develop. 

For example, poor drainage may result in damage to a plant's roots. This in turn can result in reduced vigour, opening the plant up to attack from various pests and diseases. These pests and diseases may be obvious, but the damaged roots may not be. The most important problem is called the "primary problem" and other problems which can occur as the plant weakens, are called "secondary problems." When you look for the cause of a problem, always remember; you might be looking for several answers (not just one).


ONLY 20 hours of Self Paced Online Study

It couldn't be more flexible.

At only 20 hours. this is different to our other 100 hour courses; being not only shorter and with a lower fee, but with the assessments at the end of each lesson being fully automated.

At the end of each lesson, you are given a short interactive test to undertake, to provide an indication of how your learning is progressing. 
You have access to a help desk for support from a horticulture tutor if you need it in any point in your studies.

When you finish the final lesson, you are given a more thorough automated test or examination. If you achieve an overall pass; in this final online test; you are provided with an electronic copy of a  "Certificate of Completion", with your name and the course name and date, to print and store electronically in your permanent records.

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