What’s your soil structure telling you?

Awesome plants begin with awesome soil structure.

Soil structure is a fascinating subject!  (Yes, it is so!) Generally speaking, awesome plants begin with awesome soil. Some don’t care what they grow in. (Weeds come to mind. Seems like there’s a weed for every soil.) And some garden plants actually prefer a lean, starving soil, like some herbs and succulents. Lean soil usually has a fair bit of grit in it that makes it drain quickly, leaching away minerals from the plant roots, which is not ideal for most garden plants.

Does your soil look like this?What is your soil structure telling you?

Or like this?What is your soil structure telling you?

Soil type vs. soil structure.

We discussed soil types in the last post, but this post talks about the composition of your soil. There are three main ingredients in most soils. They are sand, clay and silt.  The perfect soil embodies all three in similar proportions. It’s called loam. Loam is the soil every gardener longs for.

Major soil structures encountered in gardens.




-leaches nutrients quickly


-fine particles

-sticky when wet, (can be molded in a rope test)

-bakes hard when dry


-poor drainage

-You should not work clay soil while it is wet. It will form clods that will harden and fill you with deep regret. For goodness sake, wait until the soil has dried out to break it up! I tell you this from experience.


-tiny particles

-feels slippery when wet

-holds water

-very fertile



-mix of sand, clay and silt

-retains water and nutrients


-a dream to work with

-crumbles in your hands

-earthworms love it

-very fertile

How do you find out your soil structure composition?

A. You do a simple rope test. The aim is to make a rope from a ball of soil in your hands. First, you have to make a ball. If you can’t, then your soil is likely sandy soil. If you can make a ball but it crumbles easily, it’s likely loamy soil. (Lucky you!) It won’t be easy to make a rope from loamy soil because of it’s crumbly nature. However, if you have a lump of clay in your hands, it will easily make a rope if you add a bit of water to it. It will make any shape you want to make and hold it’s shape. (Don’t despair!)

B. You can perform a simple jar test. I filled a glass 3/4 full of water. Then I added about 1/2 a cup of soil. Three separate layers developed.  The layers are sand, silt and clay. Obviously, the heavier, grittier material will go to the bottom and the lighter, smaller material will stay on top. So, if the bottom layer is the biggest, say 80%, then you likely have sandy soil. If the layers are roughly the same, your soil is loam. If the top layer is the largest, your soil is most likely clay.

These are just two simple tests you can do on your own to get a rough idea what kind of soil you’re dealing with. For a more comprehensive soil test that tells you not just the soil structure, but the nutrients present in your soil and the pH, you should get a proper test done at a lab. They will be able to offer recommendations to fix your soil.

Soil Amendments:

Here are some great soil amendments to boost your soil health. (Just to give you an idea what is available. Always follow the recommendations provided by the lab that did your soil test.) Adding these amendments to your soil improves soil health because they invite micro-organisms which help improve soil structure.

These are all organic and safe.

N=Nitrogen; P=Phosphorous; K=Potassium

-alfalfa meal (2-1-2=NPK)

-guano from seabirds (high in N)

-soybean meal (high in N)

-fish emulsion (contains trace minerals)

-kelp meal (contains trace minerals)

-molasses (benefits include helping release N in the soil and helps micro-organisms break down organic matter)

-bone meal (Calcium and Phosphorous (P))

-blood meal (source of N)

-epsom salts (to correct Mg deficiency)

-limestone (to raise soil pH)

-sheep, cow, horse manure (high in N and good soil conditioner)

Soil conditioner

what is your soil structure telling you

Compost! Gardener’s Gold.

The best soil conditioner of all time is the one you make at home…compost.  If you don’t have a compost pile, make one! It’s free soil because everything that goes in it came from your garden or your kitchen. (No meat or bones or fat, if you don’t want to attract all the rats in your neighborhood.) It’s gardener’s gold.  It is the best thing you can ever add to your soil. It helps retain moisture in sandy soils and it loosens clay soils to make them more free-draining. (So don’t feel that you’re stuck with your sandy or clay or silty soil. You can change it!) It introduces tons of micro-organisms to your soil that help keep your soil alive. How great is that?? I, ahem, don’t have one, but I’m going to have one soon. It’ll be an experiment making one on the roof, but I want to see if it can be done. If it can, it will make me a very happy girl indeed.

What’s your take on roof top or balcony composting? And how do you maintain fabulous soil structure in your garden? Let me know in the comments below. I’m always looking for new ideas!



Leave a Reply