Let's dive into our garden soils and see what makes them tick!

Without soil we just have rock (boo!). Without soil, vegetation can’t grow.

Soil is composed of both inorganic elements and organic material (like decomposing leaves). It's this thin fragile topsoil on which our existence depends. Soil provides plants with their nutrients, keeps our plants stable by supporting the roots, and is a buffer for temperature and moisture.

There is enormous variability in soils depending on the parent rock, and the rainfall that degrades that rock and sends it downstream for sedimentation and microbial activity. Different soil types look different (colour varies from red, brown, yellow and black), and they have different depths from a few centimetres to metres deep.

Soils feel different, some are gritty, some crumbly, some feel like plasticine. And then within soils there is the stuff you can't see, like microbes. Billions of them.

So, want to know more about the soil in your yard? Knowing what type of soil you've got will help you grow a better crop of tomatoes and help figure out why that grass just isn't growing. Let’s dig deeper!

Determining your soil type

Here's how to do it

1. Dig down into your chosen plot and grab a handful of soil.
2. Place it in a glass jar filled with water, shake it vigorously then let it settle.

Once everything settles down, you'll be able to see the different layers and what your soil is made up of (you might have organic particles still floating on the top - that's okay).

The heavier particles sink to the bottom and create a sand layer. Next deposited is silt then last of all fine clay particles which hang around on top. This little experiment let's you see what ratios of each elements are combined at your place.

Sandy Soils

If your soil is straight sand then you'll notice how quickly the water infiltrates. Pick up a handful of soil and if it can't be moulded into a shape; it simply falls away, then it will be described as sandy soil.

The result of too sandy soil is that there may be insufficient moisture for establishing plants. Remember that plants can only achieve luxuriance when all elements required for growth are supplied in abundance. Anything less will mean stunted growth.

Silty/Loam Soils

Silt is somewhere between sand and clay. You might see it on floodplains. It gets deposited easily but also is carried away easily, just ask an ancient farmer on the Nile River.

Siltly/Loamyn soils are good! They're the perfect mix between sand and clay, allowing enough water retention to keep your babes moist, but not clay-y enough to drown them.
 

Clay Soils

Then there is fine clay. At just .0002mm in size it is fine, sticky and good for pottery. If your soil is heavy clay then water runs off it quickly on a slope or stays wet and gluggy when on a flat surface. Roots have difficulty pushing through compacted clays, and they can sit in the water and rot (uh oh).

You can identify if your soil is generally clay by doing the ‘snake’ test. With a handful of soil roll it and see if you can form a length without it breaking. If you can mould it like this, you've got yourself high clay soil. 

The Crumble Test

How each of the above elements are combined will show as structure. If you pick up a handful, crumble it easily and can see organic matter then you probably have the basis for good growth. Water can percolate easily, roots can penetrate, oxygen and carbon dioxide passes easily and microbes will like to call it home!

Soils hold water which is kind of handy! This ability buffers the daily and seasonal rainfall for slow release. 

If you have crumbly soils that can retain moisture, allow for gas exchange, suitable for microbes to populate, are within a reasonable pH range and have sufficient nutrients.. then you probably won't be able to stop your plants from growing!

But if you have clay, silty or sandy soils how should you amend so your plants grow well?

Amending your soil

Amending soil is easy in principle but sometimes not so easy in practise.

If your soil is too heavy clay..

If your soil is heavy clay then add sand! We're talking gritty river sand, not salty beach sand.

It takes up to 30% by volume to effect a physical change, so depending on the size of your area you might have the work cut out for you. Add chopped up vegetation like garden clippings too, this'll help break up that heavy clay. 

If your soil is too sandy..

If you have sandy soil, add organic material like leaf litter, well composted bark chips or vegetable scraps. Any vegetative material will do. The end result of mixing should be a crumbly soil.

Worms work well in aerating soils so consider proprietary worm farms like ‘Subpod’.

Let's do it!

So get out there and get your hands dirty, find out your soil type and amend as needed! Shop our Soil Correction collection here.