Here’s something that will shock most people: the difference between a flourishing garden and one that barely hangs on can be where nobody is looking — under the surface.
I’ve been designing gardens in Australia for many years, and here’s the thing: I cannot even begin to tell you how many times I have seen someone lay out hundreds or thousands of dollars on beautiful plants and hardscaping only to see it all flounder because they failed to take a little time to properly measure what they were planting into.
The subject of landscape soil testing isn’t exactly the most glamorous one. Let’s face it: It does not have the same appeal as selecting water features or planning an outdoor kitchen. But if you’re looking for hard results that don’t disappoint? This is where you should begin.
Why Most People Skip This Step (And Regret It Later)
I get it. Your client is excited. They have photos saved on their phone of their dream garden. They want to be off already. The last thing they want to hear, he says, is that you have to grab some dirt samples and wait a week.
But here is the deal – and I do mean that – garden soil analysis Australia wide is one of the smartest investments a landscaper can suggest. Consider this: you wouldn’t build a house without first determining whether the ground could hold it. Course not. Same principle applies here.
The soil is truly the base that all the rest depends on. Get that part wrong and plants wont grow, lawns become patchy, and clients ask themselves why they are paying a professional in the first. But take a look at our archive of garden design courses for professionals right here.
Classes for people who want to be pros or just better amateurs. We offer much the same as you will find on sites such as Udemy—but with specific emphasis on doing work in the field.
What Soil Testing Actually Tells You
So what information does a proper soil test give you? Quite a bit.
Soil pH levels
This is probably the big one. pH provides you with numbers to represent exactly how acidic or alkaline your soil is, on a scale from 0 through 14. Seven is neutral, below is acid and above is alkaline.
Various plants prefer different pHs. Azaleas and blueberries? They’re mad for acidic soil. If you attempt to grow them in alkaline soils, it shows: They look terrible. This is in contrast to lavender and succulents, which would rather things be a little alkaline.
Australian soils are particularly tricky. Depending on where you’re working, the acidic soils in high rainfall areas or the alkaline soils in drier regions will require different approaches to find long-term stability. Without testing, you’re guessing.
Accurate soil tests make it much easier to pick plants that are well-adapted to your soil, which means you will require fewer chanced soil amendments, a cornerstone of eco-friendly landscaping.
Nutrient levels
Your test shows how much nitrogen, phosphorus, and potassium are available – the big three nutrients plants need. Plus calcium, magnesium, sulphur, and trace elements.
Here’s something interesting: just because nutrients are present doesn’t mean plants can access them. The pH level affects nutrient availability. Even if your soil is loaded with iron, if your pH is too high, plants can’t take it up properly. They’ll show iron deficiency symptoms despite swimming in the stuff. Mad, isn’t it?
Soil texture and structure
Some tests tell you about soil composition. Mostly clay? Sandy? Somewhere in between? This affects drainage and watering frequency.
Clay soils in Sydney can be a nightmare. They hold water like nobody’s business, which sounds good until your plants are drowning. Sandy soils down in Perth? Complete opposite problem – water rushes straight through and takes all the nutrients with it.
Organic matter content
This tells you how much decomposed plant material is in your soil. More organic matter means better soil structure, better water retention in sandy soils, and better drainage in clay soils. It’s like the universal fix for most soil problems.
The Reality of Landscaping Soil Preparation
Soil prep, I once ignorantly thought was just digging in some compost when you started. More or less what you would expect.
Good landscaping soil prep is doing something useful with what the soil test told you:
- Raise pH: If soil is too acidic, add lime
- pH Adjustment: Adding sulphur If soil is too alkaline
- Amending structure: Mix in organic matter to improve drainage and moisture retention
- Blank-slate diplomacy: Sometimes you’ve got to get new soil in, because what’s there ::is too problematic
But consider a Melbourne veggie garden I added to. A soil test indicated the pH level at 4.5 – extremely acidic. We took it up to 6.5, where most veggies do well.” Night and day difference.
Without testing? You’re guessing at lime amounts. Too little wastes money. Too much of it swings you in the wrong direction. Testing removes the guesswork.
Soil pH Testing Gardens: Getting It Right
So how do you actually test gardens soil pH properly?
You have two main options: DIY kits from the hardware store or professional lab testing.
Home kits are cheap, and they work fine for getting a rough idea. But they’re not hugely accurate. You may see a reading that shows 6.8 when it’s really 7.2.” Sometimes that’s close enough. Sometimes it matters.
Professional lab testing provides you with accurate pH numbers, comprehensive nutrient analysis, amendment recommendations and interpretation. Costs the most and takes the longest, but for large landscaping projects, it’s money well spent.
Here’s what gets people twisted: You must have multiple samples from various locations. You shouldn’t just dig up dirt from one end of the garden and think that means it’s all that way. The soil is incredibly variable even over small distances.
Gather a sample from several spots, blend and get that tested. For lawn areas, go down 10-15cm deeper in garden beds. Avoid areas where you’ve recently applied fertiliser – you want to get a sense of the soil as it really is.
Different Soils for Different Folks
One of the most interesting things I’ve learned over the years is how much soil varies across Australia. What works in Brisbane won’t work in Adelaide. What’s perfect for Hobart might be completely wrong for Darwin.
- Northern tropical areas: Lateritic soils, typically acidic and nutrient-poor because heavy rainfall leaches everything out. Plants struggle despite all that rain and warmth.
- Southern regions (SA and Victoria): Alkaline soils dominate, especially inland. Acid-loving plants won’t survive without proper pH adjustment.
- Coastal areas: Sandy soils drain too fast, salt spray limits plant choices, and salt accumulation often needs addressing before planting.
This is why generic advice from overseas gardening sites can be worse than useless. American gardening blogs might tell you to do X, Y, and Z, but those recommendations are based on completely different soil conditions.
Australian soils are old and weathered compared to most Northern Hemisphere soils. We’ve got our own challenges that need our own solutions.
When Clients Push Back on Testing
Here’s the awkward bit. At times clients are not willing to pay for soil testing. They reckon it’s unnecessary. They want to get on with the fun stuff.
Here’s where you have to articulate the value. It’s $200 to test your soil. Know what costs way more?
- Dead plants: Replacing everything that died because it’s outside its comfort zone (if you’ll replace it all, why not just start with a new yard?)
- Work that was failed: Ripping out, reworking the projects with bad drainage
- Persistent problems: Wasting years arguing about things that could have been resolved at the outset
Landscapers Network professionals do things to get you the right solutions. They understand that correct soil analysis is about getting the job done right on the first visit, not inflating one’s bottom line with superfluous charges.
Share pictures of jobs past with clients where soil prep put you over the top. Most people are bribed once they realize that it’s actually a big deal, not just bureaucracy.
What To Do Once You’ve Got The Results
Getting the test results back is just the start. Now you need to interpret them and work out a plan.
Fix pH first. You can add all the fertiliser you want, but if pH is wrong, plants won’t access those nutrients anyway. Lime raises pH, sulphur lowers it. How much you need depends on your soil type and how far you need to shift.
Here’s what typically needs addressing:
- Clay soils: Need more amendment than sandy soils to change pH the same amount
- Nutrient deficiencies: Organic amendments add nutrients slowly, chemical fertilisers give a quick hit. Usually a combination works best
- Heavy clay drainage: Add gypsum to break up clay without changing pH, plus organic matter
- Sandy soil water retention: Add organic matter to help hold water and nutrients. Don’t add clay unless you know what you’re doing wrong ratios create concrete
The testing lab will usually give you specific recommendations based on your results. Follow them.
Making It Part of Your Standard Process
If there’s one thing I could say to any landscaper, it is this: Make soil testing a regular part of every job when it makes sense. Maybe not every little job, but anything with large amounts of planting or laying of lawn? Absolutely.
Make it a line item in your quotes, not an add-on. Just tell clients from the outset that this is how you work because it gets better results.” Most people appreciate that you are taking the time.
And one more thing: save records. Keep the results of tests around for each job. Photograph soil before and after amendment. Write about what you did and how plants responded. At some point, you’ll collect a lot of really valuable information about local soil conditions and what grows best.
You’re better at your job for having that information. That means you can provide better advice to future customers with similar soil. This is the kind of expertise that distinguishes professionals from mere dilettantes.
The Bottom Line
Soil testing isn’t sexy. It’s not going to make your Instagram pop. But it’s what separates landscaping from great landscaping.
If you’re a homeowner planning an extensive project in your garden, track down a landscaper who respects the importance of having soil tested. The experts at Landscapers Network know that long-term success begins with thoughtful preparation, taking a good look before making claims.
For landscapers, making soil analysis just another part of your process is not only beneficial for clients—it protects you. You’re actually dealing with real data, as opposed to guessing or hoping for the best.
When it comes to Australian garden soil analysis, there are some key things that need to be considered when assessing our soils—our ancient geology, the variety of our climate changes (from tropical monsoons in far north Queensland to year-round precipitation in short Tasmania), and the challenges presented by natural environment. Generic approaches don’t cut it. You have to know exactly what you’re dealing with in each place.
Get the basics right and everything else gets easier. Skip it, and you’re just complicating things.
Start with the soil. Everything else follows from there.
