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Soil Due diligence

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By emphasising to stakeholders the importance of getting the science right with soil, you can demonstrate that you genuinely care about the clients dream and design intent while they have the comfort of knowing that they have engaged a landscape professional that is committed to their project that goes beyond the financial relationship being embarked on.

I trust my first article sparked your interest in the overarching topic of achieving design intent and that you’re happy for me to help you attain the quest on your current, future, and past projects.

Let’s start with landing the contract and applying due diligence towards the soil during this preliminary phase.

Finally, regulatory bodies and industry have embraced the importance of working with the local site soil.

Once we amend the local soil appropriately and address any insults the previous trades may have done to it, the local soil profile is generally better suited for a healthy ecology than a media created from blended imported materials.

Naturally, there are exceptions to my generalised comments such as reclaimed land, roof gardens, podiums, and planters. These, we will leave for future discussions. But while we are on the related topic, I will mention one shining example of a garden built on imported soils.

Although Barangaroo on the shores of Sydney Harbour is growing completely on imported media, the profile was designed, engineered, and tailored to meet the exact needs of the selected species.

We will drill down into engineering soil in future discussions. For now, I invite you to take the opportunity in visiting to appreciate the results that are achieved when the client and designer listens to and acts on the professional advice specified by the soil scientist, the horticulturist and created by landscape professionals.

Have a look sometime. It is a terrific example of best practice and while you are there, pop into the Palisade Hotel next door for a deluxe Bloody Mary and the panoramic view of Sydney. (I declare no financial gain from my suggestion).

“Yes Jonathan, that all sounds wonderful and quite achievable when the cheque book is wide open, but how can I implement French champagne practices when the budget might only allow for cask wine?”

The solution to this is to educate the stakeholders that you will be applying best possible practices within the financial constraints they have provided.

Education, constant communication, diligence, and pragmatism are what’s called for in situations where the expectations exceed the level of investment the client is prepared to make.

The quote we are submitting is our opportunity to explain and educate the uninformed about the necessity of giving their plantings the best start in life.

“Hire me and it will happen”,
“Hire them and it might happen”.

Putting structural elements such as surface and subsoil drainage aside, the most important thing we can do for the long-term performance and outcomes of our botanical workmanship is to get the soil right.

Yes, plant selection is also vital, but if the media beneath them is not right from the start, we are looking at extra costs to budget, insults to the aesthetic and probable plant losses down the track.

When I am estimating projects designed and specified by other parties, if there is no line item for soil testing and consulting, I add the item and highlight the value of spending a minor fraction of the project towards getting it right in the first place.

This gets back to the value of educating the client and designer that you are the contractor they should be engaging.

By emphasising to the stakeholders the importance of getting the science right, you have demonstrated that we genuinely care about the clients dream and they can rest well with the comfort of knowing they are about to or have already, engaged a landscape professional that is committed to their project that goes beyond the financial relationship you are embarking on.

If you are not sure or confident about an element in your scope, obtain reputable advice on the issue. Telling the client that you are seeking advice because you are not quite sure usually boosts their confidence to know that you are not guessing at anything.

Demonstrating duty of care by seeking assistance is a hallmark of professional integrity, not weakness.

Let’s be frank. Most structures are relatively easy to build. Start on a solid foundation and the rest is pretty much Lego. Most licensed contractors build the same as most other contractors. The vast number of structural contractors in the market demonstrates that this is the easier part of creating the landscape asset. The skill at combining quality structures and beautiful healthy gardens is where the quality contractor rises to the top.

Regardless of whether we are working with site soil or an imported blend, please engage a soil scientist, it is they who will help to advise on achieving a suitably well drained sub and healthy topsoil.

Emphasising to the client that you embrace contemporary sciences, environmental responsibility, due diligence and duty of care will often see the tender decision extending beyond the bottom- line consideration.

So, now I have got you onboard with engaging a reputable soil scientist and we have been awarded the project, now it is time to form the ever so important collaborative relationship with the builder.

We need to get in early, develop a professional relationship with them, minimise disruptions to their schedule whilst ensuring that they come to understand and respect the integral role that we play in the overall design intent.

Collaboration will lead to education and a level of respect from the principal contractor. Having respect from other trades makes life much easier for our craft.

Just because the project has numerous trades crawling all over the place does not mean we cannot get started on waking up the soil ecology.

Let’s get in early with our soil scientist. How about we call him Murray. We will pot hole throughout the planting areas so we can inspect the profile, take samples and hopefully identify the parent material.

Murray will show us the various layers within the soil profile and help us identify potential drainage or gaseous exchange issues relating to possible layering, compaction and / or other legacies that may need addressing.

Having the client or designer there will further demonstrate our diligence and present the perfect opportunity to show the cheque signers any unseen issues that are legitimate variations.

Murray will also provide the added influence of an expert opinion in the field.

Nobody likes the discomfort caused by variations. Identifying and fixing them during the early stages while the budget is still buoyant is much easier than justifying them further down the track.

So, we have sampled and inspected our profiles. Now is a good time to rake off the myriad of pollutants and set up some affordable protective measures. There is no point preparing until we have got the test results and Murray’s advised us on amendments.

My protection methods start by raking the surface reasonably level, covering with geo fabric, and pinning in place. The heavier the material the better, as this serves to absorb the future pollutants that are likely to be spilled, scraped off or dumped on by other trades onsite.

By covering the area, it protects the soil and demonstrates to the thoughtless or uninformed trades that we are working on this area and hopefully they might show some consideration.

Depending on the budget It is often too expensive or unnecessary to protect all of the planting areas. I generally focus on the front beds and areas that are close to the building works or prone to foot traffic.

Finally, I place sheets of ply or particle board on the soil. Usually sufficient for the trades to walk on or stockpile their heavier materials.

Check out hardware’s for damaged flooring boards. Damaged yellow and green tongue often sells for $10 a sheet. This makes an affordable protective measure against compaction and improves the building site aesthetic.

Actions like this rarely go unnoticed.
In the next issue, I will discuss the soil amendment processes and materials available to us.

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