RESTORING ESTABLISHED ORNAMENTAL GARDENS

Understand How to Restore Gardens Authentically

Garden restoration involves trying to return a garden to a similar state to how it was originally conceived. For some gardens old records may be relatively easy to find. For instance, if the design was created by a designer of merit the materials may be archived in a private collection or library. If the company that created the garden is still in existence, records may be available through that company. Sometimes photographs can be found in private or public records. If people who used the property along time ago are still alive, they may remember details.

Learn the techniques behind successful garden restoration

Take this course to learn about how to restore old gardens to closely resemble the original. Find out how an understanding of garden history and styles can be significant and different ways to access records. Learn how to measure up a site, assess its current plants and hard landscape features, and decide what should be retained. Find out how to plan a restoration project and conduct risk assessments.

This course has been developed by professionals in both Australia and the UK, with the aim of being relevant throughout the world.

Lesson Structure

There are 8 lessons in this course:

1. Landscape History and Design Styles
   • Ancient Middle Eastern Gardens
   • Chinese Garden History
   • UK Garden History
   • Important English Landscapers
   • European Gardens
   • Olmsted, Burle Marx, etc
   • The Worlds First Plant Collectors
2. Surveying the Site
   • Survey Problems
   • What to Survey
   • Measuring Dimensions and Locations
   • Triangulation
   • Slope
   • Levelling Calculating Earthworks; volumes of irregular solids, using triangles, etc
3. Assessment of Plantings and Features
   • Nature of Garden Restoration
   • Assessing Plantings
   • Considering Trees
   • Assessing Garden Features
   • Considering Degradation
   • Fasteners
   • Water Problems
4. Selecting Components for Retention
   • What should be restored?
   • Renovating areas within a Garden
   • Pruning to Renovate
   • Windbreaks
5. Work Programming and Risk Management
   • Where to start renovation
   • Be Prepared
   • What Order to Work in
   • Risks to the Project
   • Risks to the Workers
6. Drainage
   • Water Logging on a Site
   • Poor Drainage Symptoms
   • Drainage Solutions
   • Reducing Erosion
   • Drainage Design
   • Understanding Gradients
   • Moving Existing Earth
   • Fixing Leaks
7. Hard Landscape Feature Restoration
   • Paving and Paving Materials
   • Concrete
   • Gravel
   • Asphalt
   • Coloured Surfaces
   • Barriers and Walls
   • Maintaining Stone and Brick Walls
   • Outdoor Furniture
   • Protecting Outdoor Furniture
   • Painting Outdoor Furniture
   • Pond Management
8. Planting Restoration and Maintenance
   • Improving Existing Plantings
   • Tree Surgery
   • Trees and Paving
   • Replacing Old and Overgrown Hedges
   • Rejuvenating an old Hedge
   • Rejuvenating Other Plants; controlling shape and size, pruning, etc
   • Rejuvenating Old Lawns
   • Perennials
   • Maintaining Herbaceous Borders
   • Controlling Weeds
   • Controlling Pests and Diseases
   • Conducting Tree Inspections
   • Chemical Safety

Aims

• Outline the history of UK garden design and the influence of plant introductions.
• Evaluate an established ornamental garden in order to determine any particular design style period, or plants of interest.
• Describe basic methods for the survey and recording of the layout and content of an established garden, and explain the importance of detailed information including assessment of site factors.
• Explain processes and the need for assessment and recording of the type, condition and future potential of a range of plantings and features in an ornamental garden.
• Explain the main criteria used to select plantings and features for retention in a restored garden.
• Explain the need and processes of analysis of collected information.
• Prepare a summarised programme for organisation of garden restoration work
• Assess risk and identify safe work practices
• Recognise and explain the visible signs of the failure of old land drainage systems and describe remedial measures
• Describe and explain the practical procedures necessary for the restoration of a range of hard landscape features.
• Explain problems which may be encountered in the improvement of retained hedges, plantings and lawns.
• Describe practical solutions for improving retained hedges, plantings and lawns
• Evaluate the use of modern maintenance techniques in established gardens.

The restoration of plantings involves both:

• Improving existing plants
• Introducing new or replacement plants

Improving Existing Plantings
The scope of this type of work may include:

1. Attending to Environmental problems

• Cutting back mature trees that are creating excessive shade, removing such trees and replanting with smaller shade creators
• Correcting soil problems such as low fertility, depletion of organic matter, inappropriate pH
• Providing temporary (and permanent protection) from weather extremes (eg. Wind breaks)

2. Removing Invasive Plants

3. Treating Plant Health Problems 

• Fungal disease
• Insect pests
• Viral disease
• Other pests (eg. rabbits, snails, mice, etc)

4. Pruning

• Install irrigation system, deep watering pipe
• Laying mulch
• Use of mechanised equipment

Replacing an Old Hedge
Sometimes the plants in a hedge are beyond restoration – the hedge may have been damaged by fire or disease. When restoring an old garden you may need to replace the existing hedge or put in a new hedge where an old one grew in the past.

Hedges and Neighbourhood Disputes
Hedges can cause disputes with neighbours. When re-planting a hedge:

• Make sure that when fully grown (in width) it will be well within the garden and doesn’t encroach on neighbouring properties. Remember that any encroaching plant material including roots may be removed by the neighbours.
• Choose plants that are easier to keep to a certain height so as to not over-shadow and exclude light to neighbouring properties or gardens in the future.
• Make sure that a new hedge will not deprive neighbours of an important view.
• Some hedges may need planning permission for removal.

Plant Choice
Some plants such as some conifers, will not tolerate constant cutting; and others simply do not develop dense, even growth. The best hedging plants usually have small leaves; though for larger hedges, larger leaved plants may be acceptable.
A large hedge will require a lot of plants - which is expensive; difficult-to-grow plants may be less desirable economically. However when replacing an old hedge in a garden restoration project it is best to choose the plants that were used originally, if at all possible or practical.

In choosing the plants, consider the following:

• Is the hedge to be evergreen or deciduous? Deciduous and many evergreen hedging plants can be pruned more regularly and vigorously then some conifers which die back if you cut into old wood.
• Informal or formal? Formal hedges need to be clipped frequently so choose a species that will tolerate frequent cutting. 
• Height - consider the plant’s natural size at maturity – for a 1 m high hedge, don’t choose plants which naturally grow to 3 or 4 m.  
• Density - a more open hedge will give better air circulation but less privacy.
• What size plants are to be used? Advanced plants can be very expensive but will give an almost instant effect; smaller plants are cheaper and often give better results in the long run.
• Quick effect - many fast-growing plants will rapidly develop into a dense hedge but will require frequent clipping to maintain a tidy shape. Some may also be short-lived.
• For a uniform hedge - buy sturdy plants of around the same size. Branching is important so it’s best to select plants dense, bushy plants to get the hedge off to a good start.
• Slow growing plants are often longer lived then fast growers. 
• Pruning - hedges such as Taxus and Juniperus have narrow leaves and make excellent hedges that rarely need more than one pruning; usually in early spring a follow up pruning in autumn is sometimes required in temperate areas.  Spruce and pine should not be cut further then the current year’s growth – prune back only part of the current growth each year. Viburnum and buckthorn are easily shaped into an arch.

Preparing the Site
The secret to a successful hedge is correct soil preparation. Once you have decided where the replacement hedge is to grow set up a string line to mark the planting positions. Dig a trench along the entire length, and add well rotted organic matter to the soil. Leave for a month or so to allow the soil to settle before planting.

Establishment
To establish a straight hedge, set up a string line and dig a trench along the length of the proposed hedge. Improve the soil with organic matter and fertiliser. Plant the shrubs/trees at the desired intervals, then water and mulch.

Depending on the size (and species) of the new plants, training should be started immediately:

• Cut back about 1/3 of the growth to encourage dense, new growth. 
• Trim the plants lightly to maintain shape and density but wait until the second year before giving another hard prune (ie. removing 1/3 off the height). 
• Once the hedge has reached the desired height, trim it two or three times each season. This is especially important for conifers, which need regular light trimming rather than hard cutting.

Spacing Plants
Work out how many plants  are needed – the spacings will be much closer than is normally recommended for plants grown in the open; for example, small-leaved box and lavender are spaced about 30 cm apart and Leyland cypress about 75 cm apart.

Hedge Trimming

• Put pegs in at either end, stretch a string line at the desired height then trim to the line to ensure a straight edge.
• Line up the edge with an object at the end of the hedge
• Mark a line on the ground at the hedge base with lime.
• Cut a little bit at a time, stand back, evaluate, and only then cut more. (You can always take more off, but you can’t put it back after removing it!)