Pruning Plants

Course CodeSGH6
Fee CodeSG
Duration (approx)20 hours
QualificationCertificate of Completion

Pruning Plants Properly can have a huge impact on how they perform.

  • A well pruned plant can produce a lot more flowers or fruit
  • A properly pruned plant can live a lot longer and look healthier.
  • Routinepruning can help manage disease, and keep plants from causing damage

Learning to Prune is more complicated though than most people would think.

This course can help you toward becoming a much more proficient pruner.

Lesson Structure

There are 9 lessons in this course:

  1. Introduction
    • Why, when and what to prune: how pruning affects plants
    • Removing broken branches, dead or diseased wood
    • Controlling the type of growth
    • Controlling the plant’s shape and size
    • Promoting healthy, bushy growth
    • Rejuvenating a plant
    • Why prune?
    • Pruning different species
    • Timing for pruning
    • What is compartmentalisation?
    • Review what you have been learning
  2. Types of Pruning
    • Cleaning out dead wood
    • Stopping
    • Disbudding
    • Deadheading
    • Pollarding
    • Removing branches
    • Crown cleaning
    • Crown thinning
    • Crown reduction
    • Crown lifting
    • Crown renewal
    • Root pruning
    • Pruning trees in general
    • Pruning larger shrubs
    • Pruning tropical plants
    • Pruning container plants
    • Review what you have been learning
  3. Pruning Tools and Equipment
    • Secateurs
    • Pruning knife
    • Loppers
    • Pole pruners
    • Hand saws
    • Trimmers
    • Chainsaws
    • Gloves
    • Review what you have been learning
  4. Pruning Hedges
    • Selecting hedging plants
    • Establishing a hedge
    • Types of hedge
    • Pruning or trimming an established hedge
    • Rejuvenating old and overgrown hedges
    • Pruning conifers
    • Other hedging techniques
    • Pleaching
    • Tapestry hedges
    • Mazes
    • Review what you have been learning
  5. Shaping Plants
    • How to develop an espalier
    • Horizontal espalier
    • Oblique palmette espalier
    • Topiary
    • Portable topiary
    • Other plants suitable for topiary
    • Single-stem topiary
    • Verdant sculptures
    • Bonsai
    • Creating bonsai
    • Pruning bonsai to shape it
    • Review what you have been learning
  6. Managing Prunings
    • Composting waste
    • Choosing plants for composting
    • Using compost to improve soils
    • Composting in home gardens
    • Indore method
    • Using lawn clippings
    • Mulching
    • How to lay mulch
    • Biochar
    • Chipping
    • Review what you have been learning
  7. Pruning for Fruit Production
    • Before buying plants consider the shape
    • Before pruning
    • Points to consider when pruning
    • Pruning specific fruits
    • Citrus spp.
    • Pruning a bush shape
    • Pruning a standard shape
    • Renovating an old citrus tree
    • Open vase shape formative pruning
    • Plum tree pruning
    • Pruning apricots
    • Knowing your buds
    • Review what you have been learning
  8. Pruning Roses
    • When to prune roses
    • Pruning techniques for different types of roses
    • Pruning climbers and ramblers at a glance
    • Pruning roses as standards
    • Dead heading roses
    • Rejuvenating an old rose plant
    • Review what you have been learning
  9. Compendium of Plants: how to Prune what and when
    • This section deals with a large number of plant genera, one by one, and how to prune each.
    • Summary: basic pruning guide
    • Glossary of Pruning Terminology
    • Review what you have been learning

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.

Learn to Make Better Decisions when Pruning

The best way to prune any plant depends on many different things, from why you are pruning it and the climatic conditions to the types of plant you are dealing with. Consider:

  • Location where the plants are grown (for example northern or southern hemisphere).
  • Climate (for example, tropical versus temperate). 
  • Aspect (for example north versus south facing slopes).
  • Microclimate (for example sunny courtyard or deep shade).
  • Reason for pruning (for example, ornamental appearance versus fruit or flower production, or disease reduction).
  • Health of the plant
  • Age of the plant

Pruning plants properly, and getting the best results, is a much more complex task than what the average person realises. Bad pruning can significantly reduce the quality and quantity of fruit or flower crops, and in the extreme, cause serious health problems or even kill plants.

This course can give you the awareness to avoid serious mistakes; and set you on a path to increase the quality of your pruning work, and the scope of different plants you are able to prune well.


Consider a few different plants and you will begin to see:


How to Prune Buddleia spp. (Butterfly Bush) 

Buddleia can be divided into three categories: those which flower terminally on the current season's wood, those which flower from the previous season's wood and those which flower terminally on the previous season's wood. 

Buddleia species which flower terminally on the current season's wood should be pruned back annually in spring to restrict growth and remove dead wood. The plant can be cut back at ground level or, if the growths are very vigorous, at around 0.9 to 1.2m. Buddleia species which flower from the previous season's wood, such as B. alternifolia, need annual pruning to maintain the balance between new and old growth, whereby new growth is favoured. The old shoots are cut back in midsummer after flowering. Deadwood should also be removed. Buddleia species, such as B. globosa, which flower terminally on the previous season's wood are pruned to retain the flowering wood. Weak and dead wood is cut back in late winter to early summer. An overgrown shrub can be pruned back hard, however flowering may be lost. B. colvilei is in this group. It is an upright grower which is suitable as a wall shrub. 


How to Prune Clematis 

These plants are mostly climbers. They require a support around which they can coil their leaf stalks. This could be a tree, pergola, fence or wall, augmented by a wire or trellis system if necessary. The main growths need to be tied to the support. 

Clematis falls into several different groups (usually stated as around 12) but when it comes to their pruning, clematis are generally considered as falling into 3 groups: those that require no pruning, those that require some pruning and those that require hard pruning. 

Group 1: includes clematis with flowers borne on previous year’s growth (flowering in late winter to spring). These are pruned after flowering and include C. alpina, C. armandii, C. cirrhosa, C. macropetala, C. montana. And all their cultivars. 

Group 2: flower twice a year – in late spring (on previous season’s growth) and again in late summer on new wood. Large flowered clematis generally fall into this group for example C. florida, C. lanuginosa and C. patens Prune these to build a good framework (fan out the shoots and tie them in to the frame) in the first year. Not a lot of pruning is needed after that – just cut back any diseased or damaged stems and those that criss-cross across each other, to the ground the following year in winter to early spring. At this point of time you should also cut back any rampant growth that has spread outside of the allocated space. Tie in new stems that grow after the first flower flush. You can extend flowering in this group by cutting back a few of the old flowered stems straight after flowering and then also regularly cut back the rest of the stems. Group 2 can be cut back hard if needed annually. And all their cultivars.

Group 3: These flower on the current season’s growth from mid-summer through to late autumn (late season). This group are cut back hard annually for all but the weaker deciduous climbers (e.g. C. vitalba). For climbing clematis in this group cut back all the stems about 30cm above the ground to a pair of healthy buds and remove all dead stems to ground level. Group 3 includes C. aethusifolia, C. flammula, C. integrifolia, C x joiuniana, C. recta, C. rehderiana, C. tangutica, C. vitalba. And all their cultivars.
A simple rule of thumb to remember is – in general the later the clematis flowers the more pruning it needs; the earlier the less it needs. 

How to Prune Fuchsias

Most varieties thrive on hard pruning. Cut back to the old wood in late winter, removing at least two thirds of growth. Be careful not to prune off flowers that tend to occur on tips of young shoots. They can also be shaped into a standard, espalier or as a fan. 

How to Prune Hydrangeas

Hydrangea x macrophylla (Hydrangeas, the Hortensia group)
Hydrangeas are best pruned in early spring. Remove any dead wood, thin out the branches, and remove those stems that are growing into the centre or across other branches. Remove one third to one quarter of the older wood to allow more vigorous young shoots to develop. Remove old flower heads by cutting just above a strong pair of buds. Leaving the flower heads through the winter affords protection to growth and flower buds during severe weather.  

Hydrangea aspera is a large leaved hydrangea that flourishes on a north facing wall and need no pruning.  Likewise Hydrangea petiolaris will grow very well in the shade.  Its size may need to be controlled and this should be done in the spring.  This is great plant for birds to nest in and for the invertebrates that the birds feed on.

How to Prune Rhododendrons

Rhododendrons generally do not require much pruning, apart from perhaps the removal of flower heads when the blooms fade. However, unsuitable growing conditions resulting in unhealthy growth and die back may make pruning necessary. Dead wood should be removed. Many rhododendrons respond readily to hard pruning and will regenerate with young growth. Rhododendrons such as R. ponticum can be used for screening and informal hedging. Annual pruning to restrict size should be carried out after flowering. Removal of spent flower heads is often carried out to prevent seed production and encourage new growth. Suckers should be removed close to the root.

How to Prune Rosemary

(Rosmarinus officinalis
Rosemary will respond well to cutting back, especially if the plant is young. This is best done in spring. Rosemary may also be pruned after flowering.


ONLY 20 Hours

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.