“To be a successful farmer one must first know the nature of the soil.”

Xenophon, student of Socrates (430 - 354 BCE)

How is it that something people knew back in 400 BCE is so often overlooked today?

It’s not just ancient Greek philosophers spouting centuries old pearls of wisdom, either. From Gandhi (who said ‘to forget how to dig the earth and to tend the soil is to forget ourselves’) to Roosevelt (‘the nation that destroys its soil, destroys itself’), our history is peppered with poetic statements about this nondescript, sometimes stinky, often muddy stuff we call ‘soil’.

And yet, despite the fact that we have known about its value and its power for millennia, all too often the importance of soil is entirely disregarded. From large scale farming of monoculture crops to the introduction of hoofed animals to Australia, humans have done - and continue to do - innumerable things to degrade, compact and deplete the soils of this earth. Which is a shame, because we need healthy soil a hell of a lot more than healthy soil needs us.

If we plan to continue to eat plant based life (or to eat other lifeforms that eats plant based life), we kinda need healthy soil. In depleted, compacted, thin or dry soil, most plants stand no chance. Soil provides structure for plants’ roots to spread through, it holds just enough (but not too much) water for them to drink, nutrients for them to absorb, and supports an unfathomably large and diverse range of microbes, bacteria and invertebrates.

Even if we can’t change the global attitude towards soil, we can start giving the ground a little more love in our own backyards. Feed your soil and you will notice a broad-scale change across your own garden. As your soil improves, your plants will become more resilient to pests (trace minerals and macronutrients in the soil help plants grow stronger cell walls, making them tougher). You might find your homegrown fruits and vegetables taste better too (healthier plants containing more nutrients tend to produce more flavourful fruit). Your garden’s watering requirements might decrease (healthy soil holds moisture better and for longer), and your plants will grow bigger, bloom more profusely and just generally look happier.

How do you get your soil into tip top shape?

1) You improve its structure by adding grit (if it’s clay-based) or clay (if it’s sandy)

2) You add a combination of broken down plant matter (compost and mulch) and animal manure. These ingredients contain nitrogen, phosphorous and potassium.

Nitrogen is a key component of chlorophyll (the compound that enables plants to convert energy from the sun into the sugars it needs to grow). It’s also essential for protein building, plant metabolism and reproduction. Plants that are nitrogen deficient are often slow-growing and small, with pale or yellow leaves. Although nitrogen is important, providing a plant with too much nitrogen can mean it grows fast but not strong, leading to a big but ultimately weak plant.

Phosphorous helps plants to grow strong stalks and stems, it can stimulate root development, improves plants’ ability to form flowers and seeds and to resist diseases, and helps legumes (peas and beans) fix nitrogen into the soil. It’s not always obvious if a plant is deficient in phosphorous, although it’s usually associated with generally stunted plant growth.

Potassium is key for plant growth and reproduction. Providing a plant with enough potassium improves the overall quality of the entire plant. It helps the plant resist diseases and build resilience to fluctuations in the environment (e.g., having too much water or not enough), and leads to better root growth and more prolific fruiting. You might be able to tell if a plant is deficient in potassium by inspecting its leaves - a common symptom of potassium deficiency is a browning of the outer edges of the leaf, or a leaf that is pale or yellow with dark green veins.

The good news is that even though all this might sound a bit complicated, really you just have to put a crapload (hehe manure pun) of manure on your garden beds and top it off with a nice thick layer of mulch (I like lupin mulch, but you could also go for pea straw - just avoid those really chunky, heavy mulches - they break down too slowly and rarely add back many nutrients into your soil).

Basically, George was right. When you consider the other choices, manure is actually pretty refreshing.

As if that wasn’t enough science for one day, I’ve made you another handy dandy infographic to summarise everything you need to know about soil improvement. From pea straw to worm poo to rock dust, if you’re looking to get your soil be-boppin and ready to go, this guide will be your… well, guide.

Grab it via the download link below and get ready to shove your fists joyously into the earth in search of Cobalt, nitrogen-fixing bacteria and (quite possibly) the meaning of life.

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