Learn to grow plants organically and help the environment in this online course. Create healthy sustainable, green gardens through distance learning.

Course Code: BHT302
Fee Code: S2
Duration (approx) Duration (approx) 100 hours
Qualification Statement of Attainment
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Go Natural with Gardening or Crop Production

  • Learn to plant food, understand what is organic food, and more
  • Indulge your passion, work in horticulture, expand your gardening skills
Learn from an international team of course writers and tutors including:
  • John Mason - 50 years in horticulture: author of Sustainable Agriculture, published by Landlinks Press (CSIRO), Garden Editor Home Grown Magazine, Board Member Australian Garden Council, Fellow Institute of Horticulture (UK), Fellow Australian Institute of Horticulture.
  • Maggi Brown - former Education Officer, HDRA, Ryton, Life member of "Garden Organic"
  • Adriana Fraser - organic enthusiast, 35 years organic growing experience, consultant, teacher, writer for many publications.

Is Organic Really Healthier?

  • Organic growing will avoid using undesirable chemicals or anything else that can contaminate people or the environment; and it's obviously healthier to avoid undesirable contaminants.
  • Organics also uses manures, mulches and other organic materials that may otherwise have been waste -and that has to be healthier for the environment (and in turn healthier for all of us who share the environment

When you grow organically though, you are increasing (or at least sustaining) the amount of organic material in the soil. Soils that have more organic material tend to remain more stable. They heat up and cool down more slowly. They contain more of the necessary microorganisms that are needed to make plants grow well, and they are better able to supply plants with micro nutrients needed to see plants grow and produce the best crops.   Opinions will always differ on how beneficial organics really is; but there is no doubt that there are some indisputable advantages.

Lesson Structure

There are 10 lessons in this course:

  1. Introduction
    • Scope and Nature of Organic Growing
    • Definitions
    • Influential People in the Organic movement: Lady Balfour, Sir Albert Howard, Jerome Irving Rodale
    • Different Ways to Garden Organically. Biodynamics, Permaculture
    • Resources
  2. Plant Culture
    • Different Cultivation Methods
    • Crop Rotation
    • Green Manure
    • No Dig Culture
    • Not TillPlanting into Grass
  3. Understanding Soils
    • Physical and Chemical Soil Properties
    • Soil Profiles
    • Identifying Soil Type
    • Soil Structure
    • pH
    • Cation Exchange Capacity
    • Buffering Capacity
    • Soil water and air, temperature, humus, etc
    • Organic Matter
  4. Fertilizers and Plant Nutrition
    • Organic Fertilisers; scope, nature, comparing different types of fertilizer and manure
    • Animal Manures
    • Seaweed and seaweed extracts
    • Liquid Feeds in Organics
    • Rock Dusts
  5. Management
    • Importance of Soil
    • Cultivation Techniques and their affects on soil
    • Cover Crops
    • Using Cover Crops
    • Green Manures as Cover Crops
    • Nitrogen Fixation
    • The Rhizobium Bacteria
    • Mycorrhyzae
    • Composting
    • Compost Bins
    • What can be Composted
    • Carbon Nitrogen Ratio
    • Compost heap conditions; cold and hot heaps
    • How to build a compost heap
    • Using Compost
    • Water in the Soil; infiltration, retention, when to water, period of watering
  6. Pests and Diseases
    • Pest and Diserase Prevention
    • Management Techniques; early intervention, using predators
    • Allowable inputs
    • Understanding Plant Problems
    • Disease Lifecycles
    • Review of Disease Types and their management
    • Viruses
    • Review of Pests and their management
    • Review of Environmental Problems and their Management
    • Companion Planting
    • Nutrient Accumalating Plants
  7. Mulching
    • Scope and Nature
    • Mulching Materials
    • Living Mulch
    • Weed Management, preventative measures, other weed control methods
  8. Seeds
    • Organic Seeds
    • Reproduction
    • Pollination and preventing cross pollination
    • Choosing Seed Plants for Vegetable Crops
    • Collection, cleaning, storing seeds
    • Sowing
  9. Vegetable Growing in your locality
    • Site Selection
    • Planning the Crop
    • Getting the most from a Vegetable Plot
    • Sowing Vegetable Seeds; outdoors, indoors
    • Transplanting Seedlings
    • Crowns, Offsts, Tubers
    • Selected Vegetables, their culture, production, harvest, etc
    • Broccoli
    • Brussels sprouts
    • Beetroot
    • Silverbeet
    • Cabbage
    • Capsicum
    • Carrots
    • Cauliflowers
    • Celery
    • Chicory
    • Cucumbers
    • Egg plants
    • Kohl rabi
    • Leek
    • Lettuce
    • Onions
    • Parsnips
    • Potatoes
    • Pumpkins
    • Radish
    • Spinach
    • Turnip
    • Tomatoes
  10. Fruit Growing in your locality.
    • Establishing an Orchard; site, climate, water
    • Designing an Orchard
    • Soil Management for Organic Orchards
    • Winter Chilling, Pollination and other fruit set factors
    • Choosing Fruit Varieties
    • Temperate and Cool Climate Fruits Review
    • Review of Tropical and Sub Tropical Fruits
    • Vine Fruits
    • Berry Fruits
    • Nuts


  • Explain the concepts and principles of organic growing, including the common techniques
    • used in organic growing systems.
  • Explain the concepts and principles of organic growing, including the common techniques
    • used in organic growing systems.
  • Determine soil management procedures, which are consistent with organic growing
    • principles.
  • Determine soil management procedures, which are consistent with organic growing
    • principles.
  • Determine soil management procedures, which are consistent with organic growing
    • principles.
  • Explain how pests and diseases are controlled using organic growing principles
  • To determine appropriate mulches for use in different organic growing situations.
  • Determine the appropriate use of seed propagation, in organic plant culture.
  • Plan the production of an organically grown vegetable food crop
  • Plan the production of an organically grown fruit crop

Tips for Growing Organic Fruit

Most fruits are a more long term proposition than vegetables, and can take considerably more space, so think carefully before deciding which fruits you might grow. Most common deciduous tree fruits take at least 3 to 4 years to crop well from planting. Strawberries crop well in the first year. Blueberries take several years to produce strongly. Walnuts and chestnuts can take 5 to 7 years before you get reasonable crops. Almost all tree fruit will bear good crops earlier if the fruit are removed for the first few years to allow the plant to establish properly. There are some exceptions - pawpaw for instance crops within one year.


As with soil management for any type of cropping, soil management in an organic orchard has two main aspects:
  1. The way changes in the physical structure of the soil are controlled.
  2. The way chemical changes in the soil are controlled.
In dealing with these things you must consider everything that might bring about changes in the soil, and try to foresee the implications of these changes in the long and short term. Factors which influence this include: Climate (including microclimates), fertilising, watering, cultivation, plants species grown, micro-organisms, insects and other living things in the soil, compaction caused by machines and people, and soil ameliorants i.e. lime, composts, gypsum etc. and neglect. Most of these factors were covered in earlier lessons however orchards are often exposed to heavy machinery so compaction can be an issue. Neglect, is also more prevalent in orchards ie. the trees are planted and left to grow without further attention to soil fertility. Orchards need organic fertility inputs to avoid trees mining the soil, depleting it of nutrients.
Amount of NPK Removed by Mature Plants per Year
  • Apples 39kgNitrogen 10kg Phosphorus and 71kg Potassium
  • Kiwifruit 24kg Nitrogen 3.5kg Phosphorus and 48kg Potassium
  • Peaches 76kg Nitrogen 11kg Phosphorus 96kg Potassium
Fertiliser Application
When choosing organic fertilisers for fruit trees, consider the fertiliser’s nutrient content as well as the trees’ requirements for major and minor nutrients. Organic fertilisers can be highly variable in their composition; for example, animal manures vary according to the type of animal and their diet. Composted materials have lower concentrations of nutrients than fresh materials - however composts are a more balanced source of nutrients, especially of trace elements.
Soil Covers
The orchard floor is a living biological ecosystem that must be managed to the benefit of the crop and to the broader ecosystem of the region. Many early orchards were grown as a multiple cropping system, even today some are still done this way. In the USA (especially in young orchards) you can still occasionally see hay or wheat crops grown between the trees. Root distribution and how it is affected in orchards is poorly understood. Root growth is affected by soil profile factors, water distribution, fertiliser placement and tree planting density. The shoot activity is controlled by root activity. Improved understanding of cover crop management and how it affects root distribution will improve the overall orchard management.
Advantages of Cover Crops
  • A growing cover crop transpires soil water; thereby decreasing soil moisture, increasing humidity near the crop and lowering the temperature. A dense cover crop insulates the crop against temperature changes.
  • Prevents soil erosion, compaction and subsequent water runoff by improving soil physical properties. Cover crops or grass also aid the rapid moisture penetration on flat surfaces during heavy rain.
  • Cover crops provide a firmer base for orchard equipment when soil is wet.
  • Shorter-growing species will provide less shelter for rodents and require less mowing.
  • Cover crops can be used to host pest predators
  • Cultivation damages roots.
  • Under mown turf, you find a better organic matter status.
  • Trees grow better if the soil without competition.
  • Plants growing below trees or vines compete for water and nutrients
  • May sometimes inhibits root growth.
  • May increase disease if not well chosen i.e. dandelion is also a reservoir for the tomato ring-spot virus, which causes disease in apples. The cover crop's relationship to pest control is a complex and poorly understood one.
  • Working conditions are more pleasant in an area covered with grass than one with only bare ground.  If you have cover crops blooming at the same time as the main crop, bees might be attracted away, leaving the crop un-pollinated.
  • Cover crops compete for water and nutrients, with no grass or weeds to compete for nutrients fertiliser applications are more effective.
  • Lower humidity occurs over bare ground than over grass or weeds and this helps discourage fungal disease.
  • Bare soil absorbs more heat during the day and gives out more at night. The more rapid air drainage over bare soil may also help to reduce frost on sloping ground by allowing the cold air to drain away during the night.
Protecting Fruit
Excessive cold might not cause any obvious damage to fruit trees but if you look carefully, you may see that the fruit buds have withered or dropped, and that can significantly affect your crop in the coming season. Some cold is good though - many fruit trees need a cold spell to get the fruit buds to form, but the same fruit trees can suffer if a frost occurs late in winter, especially if the buds have started to swell or open. Protect fruit trees by covering with shade cloth, applying thick layers of mulch, using irrigation at times of frost, or using fans to generate warm air.


To maintain a healthy orchard adopt sound cultural practices to encourage vigorous growth which will help to minimise risk.
  1. Plant trees that are botanically unrelated to create biodiversity
  2. Plant disease resistant species; many older ‘non-hybrid’ varieties have natural resistance to pests and diseases which has been lost in many modern cultivars which are bred for yield increases.
  • Some disease can carry-over in the soil – to reduce disease problems in old orchards, do not replace trees with those from the same family.
  • Soil cultivation should be kept to a minimum (and should be avoided on steep slopes) but is a way of disrupting the life-cycle of soil pests and diseases. Take care to cultivate at the correct time and soil moisture.
  • Vary harvest time – choose cultivars that are harvested at a different time to the prevalent pest’s peak period. Select harvest time to avoid the crops most vulnerable pest period.
  • Spacing is important in crop protection. Close spacing affects the growth of the tree, can help beneficial species spread but can also cause fungal disease through reduced air movement.
  • Prune trees of dead or diseased material to discourage disease spread and to encourage vigorous, healthy new growth.
  • Orchard hygiene - remove fallen fruit, remove old fruit still on the trees and avoid mummified fruit which spreads fungal disease. Use poultry to clean-up under trees.
  • Keep orchard borders clean and mown to reduce pest migration and weed introduction.
  • Use naturally occurring biological controls (approved for use in organic orchards) ie. naturally occurring cultured organisms e.g. Bacillus thuringiensis
  • Encourage, maintain or conserve naturally occurring predators by planting a mix of desirable plants to border (or within) the orchard. For example parasitic wasps are attracted to plants in the Apiaceae family - apples are sometimes under-planted this way to discourage codling moth.
  • Use mechanical controls such as traps; corrugated cardboard bands placed around the trunks of trees (for codling moths), bird netting or paper bags to exclude birds, bats or flying foxes (in some regions), approved sticky traps etc.
  • Grow resistant varieties. 
Grafting is often used to grow fruit trees on rootstocks which resist soil inhabiting pests and diseases, or poor soil conditions that reduce the vigour of the plant making it more susceptible to pests and diseases. 
  • Plant chives or garlic in a circle around the butt, under your fruit trees. This is believed to be a long term treatment, with strong evidence to support its effectiveness, particularly under peaches where it controls peach leaf curl.
  • Allow poultry to roam ('free range') beneath your fruit trees to help control pests, and to add valuable manures to the soil. BIRDS Do the birds get the fruit before you do?
  • If so, there are some things you can do about it:
  • Netting
  • Scare Crows
  • Plastic bags hanging in the tree.
  • Cats in a garden will help scare the birds away (but give the birds a fair go plenty of open space around the tree will make it difficult for the bird to be caught, and difficult for the bird to get near the tree without being seen).


 Anything can be grown organically - not just fruit, but also vegetables, herbs, nuts, berries, grain and fibre crops, or any other plants.

This course will open your eyes to techniques that can be used to get just as good results without chemicals. Once you understand the dynamics of nature and how plants grow; you can begin to experiment with growing all sorts of different plants, all sorts of different ways, to refine your techniques according to your own local conditions.

This course will enlighten you, raising your awareness of what is possible, what is easier to achieve and raise your awareness to a level where you can make better decisions about growing anything organically in your locality -on a small scale, or on a large scale.



The interest in organics is once again expanding. There are a lot of opportunities for all sorts of work in this field.

  • As a gardener - people are rapidly turning to organics as they realise that the amount of chemicals floating around in our atmosphere is a result of our heavy handed approach in the past.
  • As a grower of organic produce - not everyone has the time or inclination to grow their own food but many would still like to eat organically grown produce - the market for organic produce is expanding as people's awareness also expands.
  • As a garden consultant - some people don't have the time to study themselves but would still like to have an organic garden; for some people just advice is enough, others like to employ an expert to install and plant edible gardens.

The people behind this course are all passionate about organics and have a wealth of experience behind them - tap into this experience. Our tutors are there to encourage, advise and help you through your course!




Course Contributors

The following academics were involved in the development and/or updating of this course.

John Mason (Horticulturist)

Parks Manager, Nurseryman, Landscape Designer, Garden Writer and Consultant.
Over 40 years experience; working in Victoria, Queensland and the UK.
He is one of the most widely published garden writers in the world; author of more than 70 books and edito

Adriana Fraser (Horticulturist)

Adriana has worked in horticulture since the 1980's. She has lived what she preaches - developing large gardens and growing her own fruit, vegetables and herbs and making her own preserves.
In 1992 she formalised her training by graduating with a certif

Maggi Brown

Maggi is the classic UK "plantswoman". She can identify thousands of plants, and maintains her own homes and gardens in the Cotswolds (England), and near Beziers (in Southern France). Maggi is regarded as a leading organics expert across the UK, having w

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