Propagation I

Course CodeBHT108
Fee CodeS3
Duration (approx)100 hours
QualificationStatement of Attainment

Develop your broad skills in plant propagation.

For people who work in the nursery industry, or are enthusiastic amateurs with a broad interest in propagating plants.

You will visit or contact various sites, such as nurseries, propagation equipment suppliers and other propagators, to observe, inspect or discover things about probagation. Through these contacts you will develop an awareness of workplaces and practical applications of the subject.

This course was formerly known as Advanced Propagation. The name was changed in 2003 and the course upgraded to cover additional requirements set down in the Royal Horticultural Society Advanced Certificate and stage I of their Diploma in Horticulture

Lesson Structure

There are 10 lessons in this course:

  1. Introduction to Propagation
    • Asexual and sexual propagation
    • Aseptic Micropropagation, Runners, Suckers, Layering, Separation, Division, Grafting, Budding, Cuttings, Seed
    • Genotype versus Phenotype
    • Plant life cycles -phases of the sexual cycle; phases of the asexual cycle
    • Annual, Perennial, Biennial Life Cycles
    • Propagation Terminology
    • Nursery production systems
    • Operational Flow Chart for Seed Propagation
  2. Seed Propagation
    • Seed Sources
    • Maintaining Genetic Identity of Seed -Isolation, Rogueing, Testing, Hand Pollination
    • Hybrid Seed Production
    • Storing Seed
    • Types of Seed Storage
    • Seed Biology -Endospermic, Non Endospermic
    • Dormancy Factors Affecting Germination
    • Germination Treatments -boiling water, stratification
    • Terminology
    • Seed Raising Technique
  3. Potting Media
    • Characteristics of Potting and Propagating Media
    • Media derived from rock or stone
    • Media derived from synthetics
    • Organic Media
    • Soil Media
    • The UC System
    • Chemical Charagteristics -eg. pH, Cation Exchange Capacity, Salinity, Conductivity
    • Laboratory Testing of Media
    • Physical Characteristics
    • Potting Mixes
    • Propagating Media
    • Nutrition at the Propagation Stage
    • Nutrition Management and Fertiliser Application
  4. Vegetative Propagation I
    • Reasons to propagate by cuttings
    • Types -softwood, hardwood, semi hardwood, herbaceous
    • Stem Cuttings, Tip, heel, nodal, basal
    • Leaf and Leaf-bud cuttings
    • Cane cuttings
    • Root Cuttings
    • Bulb Cuttings
    • Hormone Treatments for Cutting Propagation
    • Other Cutting Treatments; basal wounding, anti-transpirants, fungacides, disinfectants, mycorrhyza, etc
    • Artificial Light for Propagation
    • Cutting Propasgation Efficiency
    • Rockwool Propagation
  5. Vegetative Propagation II
    • Care of stock plants
    • Layering
    • Division
    • Terminology
    • Managing Watering
  6. Vegetative Propagation III
    • Terminology
    • Budding and grafting
    • Reasons for Grafting
    • How a Graft forms
    • Grafting Techniques; Types of Grafts
    • What Plant to Graft on What
    • Grafting Materials
    • Root Grafting, Bench Grafting, Soft Tissue Grafting
    • Establishing Rootstocks
    • Tissue culture: Applications, Problems, Nutrient Media, Cleanliness, Growing Conditions
    • Tissue Culture Procedures and Techniques
    • Laboratory Requirements
    • Terminology
    • Biotech applications in Horticulture
  7. Propagation Structures and Materials
    • Growing in a Greenhouse
    • Growing Structures: Types of Greenhouses, Cold Frames, Shadehouses
    • Propagating equipment -Heaters, Bottom Heat, Misting, Light Control, Benches etc
    • Managing a Greenhouse
  8. Risk Management
    • Nursery hygiene
    • Risk assessment and management
    • Safety -tools, equipment handling, electricity, etc
    • Pest and Disease Management
    • Environmental Problems and management
  9. Nursery Management I
    • Plant modification techniques
    • Management policies
    • Keeping Propagation Records
    • Nursery Production Systems
  10. Nursery Management II
    • Nursery standards,
    • Cost efficiencies,
    • Site planning and development

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

  • Develop the ability to source information on plant propagation, through an awareness of industry terminology and information sources.
  • Plan the propagation of different plant species from seeds, using different seed propagation methods.
  • Plan the propagation of different types of plants from cuttings, using different cutting propagation methods.
  • Plan the propagation of various types of plants using a range of propagation techniques, excluding cuttings and seed.
  • Determine the necessary facilities, including materials and equipment, required for propagation of different types of plants.
  • Determine a procedure to minimise plant losses during propagation.
  • Determine the management practices of significance to the commercial viability of a propagation nursery.
  • Design a propagation plan for the production of a plant.

WHAT YOU WILL DO IN THIS COURSE

As with all of our courses, the work you undertake is far more than just reading and remembering what you read. Here are some examples of things you do in this course: 

  • Test soils to determine characteristics which would be valuable to management of any given soil in a horticultural situation
  • Identify sandy loam, silty loam, and clay loam soils by feel; and pH testing by soil indicator; and relate to plant selection
  • Identify and sow a range of different types of seeds, in different situations, in a way that will optimise successful propagation.
  • Propagate a range of plants using different vegetative propagation techniques
  • Pot up and provide after care for a range of propagated seedlings and cuttings.
  • Plant a range of (different types) plant material.
  • Maintain the desired growth type and habit for a range of plants.
  • Identify significant woody plants including: Trees; Shrubs; Groundcover; & Conifers
  • Identify a range of significant plant problems including pests, diseases and others.
  • Identify a range of non woody and indoor plants of horticultural significance.
  • Conduct a risk assessment of a horticultural workplace to determine safe working practices and select appropriate personal safety clothing and equipment

 

 
How are Plants Propagated?
 
Different plants are propagated in different ways.
This course gives you a foundation for growing your knowledge of propagation techniques both in a generic sense, and with respect to a range of different genera (or types of plants). Learning how to propagate specific plants is not something that can be learnt quickly; but an understanding of the principles and generic techniques; combined with experience will develop a capacity to make informed and reasonable decisions about how you might attempt to propagate most types of plants.
 
As an example; here are some tips from out horticulture tutors; relating to how you might propagate Banksias.  
 
Banksias are spectacular flowering plants from the Protea family; almost completely indigenous to Australia.They are grown both as garden plants and cut flowers; widely across Australia, but increasingly in other countries as well. Some species are relatively easy to propagate, and grow on afterwards; but many species are difficult, and may need to be cultivated a particular way if you are to be successful.
 
Banksias may be propagated by seed, cuttings, tissue culture or grafting. Seed propagation is the easiest and the way most nurseries have (traditionally) grown Banksias.
 
The seed is large and winged and released from cone like fruits, usually after application of heat. In the wild, seed will be released in large amounts after a fire (B. marginata and B. integrifolia are exceptions to this rule). Cones may not open naturally for many years, even though seed could be viable inside.
Even though the flowers spikes are large and crowded with flowers only very few flowers develop fruit (seed) – in some species the flowers spike will often not produce seed at all. Therefore the quantity of seed obtained per kilogram of fruits is much less than many other plants, and this fact makes the seed relatively expensive to acquire (in terms of cost or time). A wide range of Banksia seed may be purchased from Australian Native seed merchants.
 
Collect seed cones when seed is ripe, but before seed drops (for some varieties this is easy, for others, there is a relatively short period when seed can be collected). 
 
Seed remains viable longer if stored in cones (but cones can be prone to insect attack and may need to be treated with a pesticide). 
  • Store seed cones in a cool place. When ready to plant, place cones in a warm place for them to open and release seed. If seed does not release easily, soak the cone in water for 2 days then place in a warm place immediately. 
  • Seed should be sown into sterile propagating media (eg. 75% coarse sand and 25% peat), then covered with up to 0.5cm of the same media.
  • For most Banksias, germination will occur if maximum day temperatures are around 18 to 25 degrees Celsius. Some have lower or higher optimum temperatures for germination. For example B. coccinea germinates best at 15 degrees Celsius. B. aculeata germinates best at 25 degrees Celsius.
  • They are best left in a pot of seed raising mix in the open or an unheated greenhouse (do not place in a heated greenhouse). 
  • Damping off diseases can be a problem during early growth, and should be closely watched. Germination can take 3 weeks to 3 months. Some species can be grown from cuttings (mainly the fine leaved types such as Banksia ericifolia).
  • For most species, growth is best following germination, at temperatures around 23 to 26 degrees Celsius.
 
 
Banksias from Cuttings
Some Banksia species have been grown successfully by cuttings when treated with root promoting hormones (eg. some West Australian species have formed roots when treated with 8000 to 12000 ppm IBA).
Other factors influencing successful rooting include temperature (a root temperature of around 25 degrees Celsius seems generally appropriate), ventilation (do not crowd pots in a propagating bed, and do not crowd cuttings in a pot), a clean disease free environment, and minimal humidity (capillary watering may be worth experimenting with). Rooting generally takes up to 6 months to occur.
 
 
 
Tissue Culture
Tissue culture has been used successfully to propagate some Banksias, however there has to date always been difficulty in transferring plants from the laboratory into soil. The technique may have potential, but is not yet used commercially, to our knowledge.
 
 
 
Grafting
Grafting involves joining parts of plants in a way that they will grow together and remain united as one plant.  The part of the graft combination which becomes the upper part of the new plant, is called the scion.  The part which becomes the bottom part is called the rootstock or stock.  All methods of joining two plants together this way are forms of grafting however, when the scion is only a small piece of bark containing a single bud, the technique is called "budding".
 
 
 
How a Graft Forms
There is a mass of growth cells in any plant between the bark layer and the inside wood of the plant.  That layer is called the cambium layer. The cambium is the region where growth is happening, and as such, when you graft you MUST ensure that the cambium of the stock contacts the cambium of the scion. This is the single most important thing to learn about budding and grafting.
 
The usual sequence in the formation of a graft is as follows:
1. Freshly cut cambium tissue of a scion is brought into contact with freshly cut tissue of a stock.
2. The section where the union has been made is sealed (possibly with plastic tape - maybe with wax or grafting mastic).  This sealing does two things - it holds the graft in place, and it prevents drying out of the cut tissue.
3. The outer cells in the cambium region grow together producing a callus.
4. New cambium tissue is produced between the two different varieties.
5. When growth is seen to have taken place, the plastic tie or seal on the graft union may be removed.
 
 
General Grafting Hints: 
  • Keep Records
  • The stage in the plant's lifecycle is critical
  • Root and scion maturity is critical
  • The correct technique is critical
  • After care is critical
  • Keep your reel of grafting tape tied around your neck (It can become contaminated if it is left lying on a bench or put down on the ground in the field).
  • Don't graft wet plants (A dry scion and dry rootstock give the best results). When you graft wet material you are more likely to get bacterial soft roots and other problems.
  • Grafting young onto old works but grafting old onto young does not work.
  • General information on grafting theory is abundant but information on grafting practice related to Banksias may be scarce.
 
Many of the West Australian Banksias have proven very difficult to grow in the eastern states of Australia and elsewhere. Grafting onto seedlings of B. integrifolia, spinulosa or marginata have produced good 
 
 
 

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