Few things in life are as rewarding as being able to sustain your garden on compost you created. The hours spent collecting, sorting, piling, and mixing have finally paid off, and you now have healthy compost. Before adding it to your gardens, you will want to find out how to tell if your compost is ready.
The best way we have to check whether compost is healthy and ready is through our 5 senses. The more years you spend composting, the more in tune with the soil composition you will become, but until then, check out this guide to find out what homemade compost should look like.
How to Tell if My Compost is Healthy?
The best way to tell if a compost pile is ready is to look at it and see what organic materials are abundant. There will immediately be tell-tale signs if the compost is not yet finished. Brown materials, dry leaves, grass clipping, and coffee grounds may still be noticeable in the compost pile.
Kitchen scraps like food scraps and vegetable scraps are common sights in healthy compost piles. Green materials and brown materials need to be combined in the correct carbon-to-nitrogen ratio in order for compost to be completely healthy.
When a compost pile is ready to be used as finished compost, any large items remaining can be sifted out. The remaining brown materials can be added to a new compost pile.
By taking the time to study our compost and using our sight, touch, smell, taste, and even hearing, we can tell how nutritious our life-giving concoction is for our happy gardens. Don’t go crazy and start shoving dirt in your ears or throwing the soil in a blender. Just perform some of these tests to get a good vibe of your pile’s pulse.
What Does A Healthy Compost Look Like?
Healthy compost will be dark brown to black in color with an array of various substrates peppered in. The rich color of the soil is punctuated by a range of sizes of soil particles that cling together gently. A handful of compost will crumble and fall out of a clenched hand.
Inside the compost, you should see a myriad of bugs, worms, and microorganisms scrambling just under the soil’s surface. Large pieces of organic matter that haven’t broken down yet can be seen scattered about. These waste scraps that won’t make it into finished compost can be strained through a wire mesh and added to innoculate future piles.
The main way you would know if your compost is healthy is by examining the final finished soil. Once it’s ready for the plants, you can clearly tell whether it is the deep color, proper structure, and the correct variety of materials. That is how healthy compost should look.
What Does A Healthy Compost Feel Like?
Vision alone cannot guarantee that your compost is healthy and ready to go. There are certain components of compost that are best observed via touch. Moisture content and temperature are two conditions that can be measured by feeling the compost.
You can test the temperature of the compost by resting your hand against the pile. Throughout the composting process, piles can reach up to 160℉, so make sure it’s not that hot before grabbing a handful.
When a compost pile is still very hot, it is a sign the decomposition of organic matter isn’t completed yet. It is not a good idea to use compost at this stage in your garden because it will harm your plants. The optimal time to use compost is when the temperature has been ambient for several days to a week.
Healthy compost also needs the correct moisture level. Compost that is too wet or too dry will not be healthy and could harm plants and start to smell. The easiest way to test the dampness of compost is to pick up a handful and squeeze it into a ball. Slowly open your hand and observe what you see and feel.
Healthy compost should briefly hold together and then release like a sponge and fall apart. It will crumble out of your hand with only slight residue sticking to your palms. The soil should not be so wet that it clumps nor so dry that it never holds together and leaves your palms bare.
What Does A Healthy Compost Smell Like?
Smell isn’t necessarily the first sense we think of when checking the doneness of our compost, but it can be incredibly helpful, especially if you are working with a larger pile. A healthy compost has a distinct smell that is both pleasant and recognizable. Unhealthy compost also has a distinct, albeit pungent, odor as well.
To tell if compost is finished by smell, pick up a handful and take a whiff. The smell should be sweet and mossy. It should fill your sinuses with an earthy note that lingers, just on the edge of unpleasantness. Occasionally some of the bugs may give off a stench not dissimilar from rot but not as foul.
Unhealthy compost will have the smell of nitrogen, methane, and wet grass, which permeates the air around the pile. As the compost matures, the smells should lessen, and the stink of decay should subside. This is an indicator that your pile will be ready soon or that it is a great time to flip the pile and restart the decomposition cycle.
What Does A Healthy Compost Taste Like?
Like any connoisseur, the sense of taste can be used to rate the finish of aged and mature compost. Although I don’t recommend dining on dirt, a small sampling of soil may lend you some insights.
Healthy compost should have already passed the smell test before tasting is considered. If it smells like it is still decaying, it’s best to keep your tongue away. If the smell is appetizing, then a simple taste can determine a few things.
There should be a range of tingles as the different metals ping around the taste buds. In the end, you are left with a flavor similar to the way it smells after it rains. The petrichor arises from microbes in the soil that produce geosmin. A musky aroma, petrichor can be experienced in the remnants of the compost’s aftertaste.
What Does A Healthy Compost Sound Like?
Sound, too, can be used to judge a compost’s health. I use sound to tell if compost has the right water retention capabilities. Sound lets you sense the vibrations water makes as it moves through the ground and can show you if everything drains correctly.
Healthy compost will have a sound similar to a stream rushing through rocks when poured into a bucket, filled with soil, and held up to your ear. You will hear soft babbling as water freely pools, saturates the soil, and finally continues flowing through.
Soil that is too porous and sandy will have almost no sound as the water quickly settles to the bottom. The wetness will saturate up from the bottom, and a small sucking sound like holes filling with water at the beach can be heard.
If your compost is too clay-dominant, then you will experience a pronounced slapping and sucking sound. As the water pools in cracks and then pressure builds when the clay grows too thick, water gets sucked through. The slurping and slapping sounds get quieter as the water settles in small pressurized chambers within the compost.
A Quick Overview of A Healthy Compost
Having a healthy compost pile feels good, and it’s good for you and your plants too. Knowing what to look for to ensure that you have a balanced pile is a must. But you also need to know what to feel, smell, taste, and listen for as well.
The chart below will give you a quick summary of what your compost should be like.
Compost Attribute | Poor | Standard | Healthy |
Looks | Uniform and cracked | Chunky and gray | Dark and varied |
Feels | Dry or wet | Hard or too clumpy | Soft and crumbly |
Smells | Bad | Nothing or decay | Sweet and earthy |
Tastes | Bad | Gritty and bitter | Metallic and musky |
Sounds | No sound, loud slurping | Slow trickle sound | Gentle bubbling |