Mason Jar Soil Testing May 12, 2015 09:13

Soil settling away happily
Gardening isn't really a new concept for me, and I usually tend to think of myself as fairly well versed in it, but the past couple of years have exposed a pretty glaring blind spot in my gardening knowledge: Soil.
I know, I know. You're thinking "Soil is kind of the basis of gardening", and you're right! It seems like I should know plenty about it, but the reality is that I've spent most of my adult life living in apartments, forced to garden solely with containers and pots. So, much as I daydreamed about my eventual future acreage, up until recently my experience with soil has been limited to the types and sizes that can be purchased and then carted home on the bus. I never had to worry about what sort of soil I was working with, because it was always fresh and new, full of nutrients, and neatly labelled on the shiny bag it came in.
And then I moved into a house with an honest-to-goodness yard. A yard with a big garden plot, one that had seen little to no attention for years and looked pretty sad. As I pointed out to my landlord, even the dandelions didn't want to grow there.
Google is my friend, and that's how I found out about the mason jar soil test. It's one of the easiest and simplest ways to see what kind of soil composition you're working with, and to find out what you might need to add to the soil in order to make it healthy.
The mason jar soil test
Soil is, at its most basic, made up of 3 parts. Sand, Silt, and Clay. You can also have chunks of rock or other debris in there, but we're ignoring those for the purposes of this test. Sand is the largest particle, silt the middle, and clay the smallest. An ideal garden soil (called loam) is approximately 20% clay, 40% silt, 40% sand. Knowing how far you are from that perfect balance will help you to decide what sort of amendments need to be added.
To check this balance, all you need is an old mason jar (taller is better - I used asparagus jars), a tightly fitted lid for it (I have a recent obsession with the plastic storage lids, so I used one of those), a way to sift out rocks and debris (a soil screen or wire mesh works well), a ruler, and some water.
Scoop up some soil from your garden bed and sift it through your screen. You can choose to take samples from multiple areas and combine them in one test, or do several jars for each area to get a more specific idea of soil composition. Fill your jar(s) about 1/2 to 2/3 full of soil, and then fill the jar almost to the top with water. Leave a little bit of headspace so that you can shake it up well.
Tighten the lid and shake the jar vigorously for several minutes until all the soil is well distributed in the water, and then set it aside for several hours. Resist the urge to pick it up and turn it. You'll have to start the process over. (Yes, I speak from experience).
Once all the soil has settled down into stratified layers, you can use your ruler to estimate how big each layer is. Sand will be the bottom, heaviest layer, Silt in the middle, and Clay at the top. I was lucky enough to be using a jar with measurements on the side, so I skipped the ruler step.
the proverbial well rotted manure
As you can see from my photo, my soil is more of a 20/20/60, instead of a 20/40/40. This means I have sandy soil, which is often lacking in nutrients, microbial activity, and doesn't hold moisture well. Luckily, the easy answer to this is to add more organic material - like compost! Cover cropping is also another valuable way to improve sandy soils. Since I don't have an active compost bin yet, my temporary solution involves a very familiar tactic.
I'll be busing home with a bag of lovely compost.