Living SoilHow healthy is the soil in your garden right now? Not your plants: your soil. Most gardeners have never really checked, because it seems like a lab job.
It is not. A spade, a glass of water and a few minutes will tell you more than you might expect. And once you know where you stand, you will know whether the changes you make are working.
The trick that makes every test useful: compare
Before the checks themselves, one tip from the research that makes all of them more meaningful: compare two patches side by side with different histories. A bed you have been mulching against one you have been digging, or the garden against the lawn next to it. The difference between them tells you far more than one sample on its own.
Check one: look at the crumb
Dig up a spadeful and break it apart. Healthy soil has a crumb like structure and breaks apart easily, with no large clods. Good topsoil is granular and resembles chocolate cookie crumbs. Large, hard clods point the other way.
Check two: count the life
A healthier soil has a darker color, more soil organisms such as earthworms, and more roots. Look for worms, their casts and their channels.
How many is enough? One farm field assessment asks for at least 3 earthworms per shovelful. That figure was written for farms, and no garden benchmark was found in the research, so use it as a rough guide and compare year to year instead.
Check three: the slake test
Drop a few small clumps of soil into a glass of water and watch. Clumps from healthier soil hold together longer. Stable crumbs, the kind that do not fall apart when wet, are key to healthy soil, because they show how well your soil holds together when it rains.
The research suggests doing it every year at about the same time, and noting how long the clump takes to break down. That gives you a simple record of whether your soil is improving.
Check four: feel for compaction
Push a wire flag, the kind used to mark utility lines, into the ground and feel how hard it resists. Try a few places, including the paths and the middle of the beds. Where it resists hardest, the soil is most compacted, and compacted soil takes in less water and restricts root growth.
Check five: watch the water
Healthy soil takes in water faster. The research method is to hammer a metal ring into the ground and pour water into it. No garden pass mark with timings was found, so this is another one to compare: the same ring, the same amount of water, two patches, and see which drinks it faster.
And trust your nose
That rich, earthy smell of freshly dug soil comes from soil bacteria. It is life you can smell.
What to do with the results
If the crumb is poor, worms are scarce and water sits on top, the soil life needs feeding and protecting. That means organic matter every year, a cover of mulch, no digging and no walking on beds. Start with how to make living soil, then check again next year at the same time. The second check is the one that tells you it is working.