Landscape designer Xanthe White has dedicated her latest book to the basics for every garden - healthy soil. She joins Kathryn Ryan to talk about her The Good Dirt and shares her tips for making sure your soil is pristine and how to get the best out of it. Her 20 years working around the world has helped to shape this book and its stunning images.
Read an edited excerpt of the interview below:
What are the organisms in healthy soil that you just want to leave be?
The soil that we want to grow a healthy garden as part of an ecology, as part of a whole cycle, like the relationship between wood and earth and mulch… even as you look at a tree, most of it is actually living underground. So what’s happening under there the more we scrape off, it’s alive. It’s got bacteria, it’s got fungus, it’s got all of these different things happening and when you scrape it back and push it to the side, you’re taking away all of that. It’s like healthy probiotics in your tummy. All of that delicate little ecology that’s beneath. And it’s our eco system too. Healthy food is healthy soil. It’s all part of it. Layering it up and letting it grow itself is where the magic lies.
What are the different soil types and what do you do with each of them?
You could go into millions of different types of soil, but what a gardener needs to know is basically, look at clay, fertile soils, sand, gravel and then modified soil, so a situation where you’ve got totally artificial soil. Lots of people have gardens in pots these days. Those are your main situations that you’re dealing with. They’re all based on the particle size of the soil. When you’ve got really fine soils, like a clay, it’s difficult to get water movement through that soil and it is also difficult to get water to move out of that soil and we all know that water is the key to all life. When you are in a sandier or gravel soil, the difficulty is in growing organic matter in that soil, so if you think about soil quite simply as these particles that the flow of water through and a build-up of organic matter through, is essential, then it’s actually quite easy to understand your own garden.
Do you water soil, or are you watering the plant?
I believe that there are certainly situations you need to water, like when you are establishing a new garden, particularly when you have planted it further towards the heat of summer, but I am quite resistant to irrigation systems. I have found more through my years of maintenance and building many gardens, we have more problems with overwatering, than we do of under watering. You really want your plants to grow and get their roots down deep and you want that mulch and moisture. You want a garden that is full of plants. Ideally green mulch is the best. A full, overflowing abundant garden is the best way to keep it healthy, so I think watering should be done very carefully and selectively and throwing a whole lot of water on a garden isn’t ideal.