When we design or plant a garden, we want our final product to stand the test of time.

Plants need to be healthy when we plant them and continue to be so year after year.

Good soil preparation is the primary reason for a healthy and successful garden.

Begin by understanding the soil you will be working with; this includes surrounding gardens, topography and micro-climate. A simple soil pH is a cheap and efficient way to help prevent problems further down the track.

Learn the history of the site you are working on. In urban areas you may need to know if the land has ever supported industries where heavy metals or other contaminants were used. In rural areas it may be that the new garden is located near an old dairy bale where the soil will have been heavily compacted by the herd or near cattle and sheep dip where the soil will have been contaminated with arsenic or DDT.

A simple step is to go to the following website to check out if the land is on the register of contaminated land: http://www.ehp.qld.gov.au/land/contaminated-land/#emr

Cut and fill sites come with their own set of problems, mainly compaction and soil strata disturbance. I will approach this in a later article.

Soil compaction is one of the primary reasons for plant failure. Check soil compaction using a simple garden fork or small crow bar. A well aerated soil will improve root penetration; addition of organic matter will increase soil fertility, water retention and soil micro-organism activity.

Examining the type of plants, including weeds, will reveal a lot about the type of soil and nutrient availability you are dealing with on that particular site.

Having a good knowledge and understanding of weeds and their requirements is often as effective as an expensive laboratory test. For example, moss is a symptom of an acidic soil due to compaction.

Observing and recording of the site conditions prior to designing and planting should be a pre-requisite of any good landscape professionals. Those are skills that are unfortunately too often overlooked or even dismissed as unreliable by members of our own profession and teaching facilities.


About Patrick Regnault
I have worked in the horticultural and landscaping industry for over 35 years in three different countries.I am a member and Registered Horticulturist with the Australian Institute of Horticulture and member of the Housing Industry Association. I am the owner of Interactive Landscapes, a successful structural landscaping and landscape design business. I believe that what gardens and gardening do is to reconnect people with the fundamental elements of nature. A good gardener will try and acquire a profound understanding of the balance of nature and endeavour to do the best to improve the environment in which the garden is situated. At Interactive Landscapes it is a philosophy that we put into practice when designing and creating a garden, no matter the size. Our name reflects this as we understand that gardens are a place of interaction. View all posts by this author »