Composting smarter

Biochar for Compost: Build Better Soil Before Spring

Your compost pile is alive. Add Biochar as you build it—or combine Biochar with compost or manure during soil preparation—to retain water and nutrients, giving microbes a porous carbon structure where they will interact, grow, and develop before planting begins. This is the key to great soil.

And if spring is already here? It is not too late. You can charge Biochar before application at any time of year.

Shop Biochar Calculate How Much You Need Talk to a Biochar Specialist →

Compost feedsBiochar holdsSoil comes alive

Microbes are the engine

Great Compost Starts With Microbes

Composting is a biological process. Bacteria, fungi and other microorganisms break organic materials down and transform them into increasingly stable organic matter. Their activity is influenced by moisture, oxygen, temperature, available carbon and nitrogen, and the physical structure of the pile.

Biochar does not replace compost, and it is not a fertilizer by itself. Its porous structure will provide surfaces and microsites where moisture, nutrients, organic compounds and microorganisms interact.

When Biochar is incorporated during composting, it is exposed to the nutrients and biological activity of the pile. This is commonly described as charging or inoculating Biochar. Silvachar Biochar is made from natural, clean organic forest wood waste and will complement many agricultural and growing methods.

Why add Biochar?

What Biochar Will Do Inside a Composting System

Biochar supports several interconnected processes within a well-managed composting system, helping retain nutrients and moisture, improve aeration, provide habitat for microbial activity, and help manage ammonia and odours. Its performance will vary depending on factors such as compost feedstock, moisture levels, application rate, and overall composting conditions.

Retains Valuable Nutrients

Biochar helps retain valuable nutrients such as nitrogen, phosphorus, potassium, calcium and magnesium, keeping more nutrients in the compost for later plant use.

Keeps more of what your compost already has.

Supports Microbial Activity

Its porous structure provides surfaces and microenvironments that interact with microorganisms, moisture and nutrients.

Long-lasting habitat that supports microbes as they cycle nutrients and make them available to plants.

Supports Airflow & Structure

Porous Biochar becomes part of the pile’s bulking structure and helps air move through the mixture.

Better conditions for aerobic composting.

Helps Manage Odour & Ammonia

Biochar reduces selected gaseous emissions while helping retain nitrogen.

It will reduce odour and ammonia losses.

The fall method

Start Next Spring’s Soil This Fall

After harvest, your garden still has months of biological activity ahead. Combine Biochar with compost, well-managed manure or another organic amendment and give the mixture time to remain moist and biologically active before planting.

Spring or summer? No worries.

It is never too late to put Biochar to work.

Charge or inoculate Biochar with compost or appropriately managed manure for at least two weeks. It will then help retain water and keep valuable nutrients closer to plant roots.

Calculate How Much You Need

Add organic material

Begin with leaves, garden waste, food scraps or another appropriate compost feedstock.

Sprinkle Biochar evenly

Add fine layers of Biochar throughout the pile—just enough to create an even black coating without forming thick layers.

Repeat the layers

Organic material → Biochar → organic material → Biochar. Build contact throughout the pile.

Keep it moist and aerated

Moist—not waterlogged—is the goal. Continue normal compost management, including appropriate turning or aeration.

Let biology do the work

Allow nutrients, moisture and microorganisms to interact with the Biochar throughout composting.

For fall soil preparation: combine Biochar with finished compost or appropriately managed manure, mix it into the growing area, and allow fall and winter moisture to help integrate it. Planning a farm, commercial composting or municipal application? Contact our team for project-specific ratios and volumes →

Spring is already here?

You Still Have Time.

Biochar does not have a deadline. Fall provides more time for natural interaction, but you can prepare Biochar at any point in the growing season.

Option 1 / Compost or manure

The Slow, Effective Charge

Mix Biochar with compost or appropriately managed manure and keep it moist.

1 part Biochar + 9 parts compost/manure

Let the mix rest for at least 2–3 weeks.

The longer Biochar remains in contact with moist, biologically active material, the better. If you are in a hurry, two weeks is a practical minimum before incorporating the charged mixture into soil.

Option 2 / Prepared liquid

The faster charge

Prepare or dilute liquid fertilizer according to its label, or use compost tea.

1 part Biochar + 1 part prepared liquid

Soak approximately 24–48 hours.

Incorporate it around the root zone or into soil. For established plants or rows, add a scoop of charged Biochar at the base or alongside the plants, keeping it close to the roots without disturbing them. Never use undiluted fertilizer concentrate unless its manufacturer permits it.

Year-round value

Biochar Is Not Just a Spring Soil Amendment

Fall

Build next season’s soil

Compost and leaf piles
Post-harvest soil preparation
Raised and new garden beds
Manure composting
Orchard and vineyard programs

Put Biochar to work before the snow arrives.

Winter

Manage organic materials

Covered compost systems
Manure storage and bedding
Poultry litter and chicken coops
Greenhouse compost systems
Preparing charged Biochar

Protected storage and incorporation help prevent loss from wind or runoff.

Spring

Prepare the root zone

Vegetable and flower gardens
Trees and shrubs
Lawns and containers
Greenhouses and nurseries
Farm planting programs

If Biochar was not prepared earlier, use either of the two charging methods explained in the section directly above before applying it.

Summer

Help inputs work harder

Active compost piles
Established beds and containers
Dry or moisture-stressed soils
Compost tea charging
Manure and odour management

Charged Biochar is ideal for helping lawns retain moisture during hot weather and municipal water restrictions.

Biochar + livestock systems

From the Barn to the Compost Pile

Biochar will work as part of manure, bedding and compost-management systems. Research has investigated its ability to adsorb ammonia and reduce nitrogen losses in manure and poultry environments.

Poultry litterChicken coopsManure pilesBedding systemsMoisture managementOdour management

Helps manage moisture, ammonia and odour in manure and bedding systems. This is not an animal-health treatment or feed recommendation.

Talk to a Biochar Specialist

Evidence, without the clutter

What Does the Research Say?

The titles stay compact so visitors can scan the evidence. Select the plus sign to expand one study at a time.

The IBI describes Biochar as complementary to compost—not a replacement. Reported potential benefits include improved pile structure, microbial activity and nutrient retention, with possible reductions in ammonia loss and odour. Results and greenhouse-gas effects are not consistent in every system.

Composting will charge or inoculate Biochar with nutrients and biology.
Studies have tested a wide range of addition rates.
Results depend on the materials and system being used.

Camps, M., & Tomlinson, T. (2015). The use of biochar in composting. International Biochar Initiative.

Laboratory, composting, greenhouse and field trials tested Biochar at approximately 2.5%, 5% and 10% by volume. Laboratory work found reductions in selected volatile compounds associated with compost emissions, while crop responses varied among crops, soils and treatments.

A 10% Biochar treatment reduced several measured compounds in laboratory testing.
The results support qualified odour and emissions messaging—not universal promises.

Gang, D., Collins, D., Jobson, T., Berim, A., Stacey, N., Seefeldt, S., Khosravi, N., & Hoashi-Erhardt, W. (2021). Integrating compost and biochar for improved air quality, crop yield, and soil health. Washington State University.

Cornell researchers found covalent bonding between ammonia nitrogen and pyrolysed carbon surfaces, helping explain how Biochar will retain nitrogen that might otherwise be lost. The mechanism supports nutrient-retention and ammonia-management messaging, but not every Biochar will retain the same amount.

Hestrin, R., Torres-Rojas, D., Dynes, J. J., Hook, J. M., Regier, T. Z., Gillespie, A. W., Smernik, R. J., & Lehmann, J. (2019). Nature Communications, 10, 664.

This meta-analysis evaluated 876 observations from 84 studies. Across the dataset, several compost-quality indicators improved and average ammonia, nitrous oxide and methane emissions decreased. Effects varied with Biochar properties and composting conditions.

Total nitrogen increased by approximately 9.5% on average.
Average ammonia emissions decreased approximately 44.2%.
Study rates must not be presented as a universal Silvachar application rate.

Zhou, S., Kong, F., Lu, L., Wang, P., & Jiang, Z. (2022). Biochar—An effective additive for improving quality and reducing ecological risk of compost: A global meta-analysis. Science of the Total Environment, 806, 151439.

A 2017–2020 study in a British Columbia Merlot vineyard tested a Biochar-compost mixture under Okanagan conditions. Treatments increased soil carbon in the upper layer in parts of the experiment, while crop and soil responses differed among years.

The local study reinforces the importance of site conditions and long-term field testing.
Its 1:1 experimental treatment served a different purpose and is not a consumer charging instruction.

Sharifi, M., & Hajiaghaei-Kamrani, M. (2022). Biochar–compost mixture and cover crop effects on soil carbon and nitrogen dynamics, yield, and fruit quality in an irrigated vineyard. Canadian Journal of Soil Science, 103(1), 200–212.

The review found that Biochar converts part of biomass carbon into a substantially more persistent form. Climate benefit depends on feedstock, pyrolysis, energy use, transport and final use, so product-specific removal figures require product-specific carbon accounting.

Lehmann, J., Cowie, A., Masiello, C. A., Kammann, C., Woolf, D., Amonette, J. E., Cayuela, M. L., Camps-Arbestain, M., & Whitman, T. (2021). Biochar in climate change mitigation. Nature Geoscience, 14, 883–892.

Biochar performance depends on feedstock, production conditions, compost materials, application rate and management.

Choose the right grade

Biochar for Every Scale of Composting

Fine / <2 mm

Fine Biochar

For lawns, sandy soils, fine blending, gardens, raised beds and applications where even distribution matters.

Shop Fine Biochar →

Coarse / 2–6 mm

Coarse Biochar

For clay and heavier soils, raised beds, trees, shrubs, landscaping and projects needing structural aeration.

Shop Coarse Biochar →

All-purpose / 0–6 mm

Compost & Soil Prep

The versatile choice for compost piles, fall soil preparation, compost/manure blends and general soil improvement.

Shop All-Purpose Biochar →

Bulk / 1,000 L+

Commercial Biochar

For farms, orchards, vineyards, commercial composters, municipalities, landscapers, nurseries and livestock operations.

Request a Commercial Quote →

Still not sure which Biochar is best for your needs? Use our Biochar Calculator to find the right grade and amount for your project.

Use the Biochar Calculator

Keep this simple

Three Practical Starting Points

Compost / manure1 + 9 parts

Keep moist; rest at least two weeks when pre-charging.

Prepared liquid1 + 1 part

Soak approximately 24–48 hours and mix occasionally.

Garden soil5–10%

Approximate Silvachar home-garden guidance by soil volume.

Good guidance matters

Biochar Is Powerful—But Not One-Size-Fits-All

Feedstock, production temperature, particle size, pH, ash content, surface chemistry and application rate all influence performance.

Work with nutrientsBiochar is not a fertilizer replacement by itself.

Charge or inoculate itCombine Biochar with an appropriate nutrient source.

Use the right amountMore Biochar is not automatically better.

Control fine dustKeep fine Biochar slightly damp during handling.

Measure correctlyWeight and volume percentages are not interchangeable.

Handle manure safelyUse appropriate food-safety practices.

Plan large projectsCommercial applications need project-specific rates. Talk to a Biochar Specialist →

Follow safe handlingUse Silvachar’s SDS and PPE guidance.

Frequently asked

Biochar & Compost FAQ

What does Biochar do in compost?+

How much Biochar should I add?+

Should I add it to every layer of my compost pile?+

Does Biochar need to be charged first?+

How long should Biochar charge?+

Can Biochar reduce compost odour?+

Is Biochar a fertilizer?+

Can I use Biochar in chicken coops?+

Yes. Sprinkle thin layers of Biochar over the wettest or most heavily travelled parts of the coop, premix it with fresh bedding, or add a light layer weekly and whenever odour increases. For a coop with approximately 20–50 chickens, two 10 L buckets will generally be enough for fall and winter, depending on how often the bedding is replaced. Use it for bedding, manure and odour management—not as feed or an animal-health treatment.

Start preparing for next season

Your Best Spring Soil Can Start This Fall.

Add Biochar while building your compost. Give nutrients, moisture and microorganisms a porous carbon structure to work with—and let the system develop before planting begins.

And if fall has already passed? It is never too late to start.

Shop Biochar Calculate How Much You Need Request a Commercial Quote →

Biochar for Compost: Build Better Soil Before Spring

Great Compost Starts With Microbes

What Biochar Will Do Inside a Composting System

Retains Valuable Nutrients

Supports Microbial Activity

Supports Airflow & Structure

Helps Manage Odour & Ammonia

Start Next Spring’s Soil This Fall

It is never too late to put Biochar to work.

Add organic material

Sprinkle Biochar evenly

Repeat the layers

Keep it moist and aerated

Let biology do the work

You Still Have Time.

The Slow, Effective Charge

The faster charge

Biochar Is Not Just a Spring Soil Amendment

Build next season’s soil

Manage organic materials

Prepare the root zone

Help inputs work harder

From the Barn to the Compost Pile

What Does the Research Say?

Biochar for Every Scale of Composting

Fine Biochar

Coarse Biochar

Compost & Soil Prep

Commercial Biochar

Three Practical Starting Points

Biochar Is Powerful—But Not One-Size-Fits-All

Biochar & Compost FAQ

Your Best Spring Soil Can Start This Fall.

Talk to a Biochar specialist.

Made in British Columbia.
Ready for your project.

How can we help?

Biochar for Compost: Build Better Soil Before Spring

Great Compost Starts With Microbes

What Biochar Will Do Inside a Composting System

Retains Valuable Nutrients

Supports Microbial Activity

Supports Airflow & Structure

Helps Manage Odour & Ammonia

Start Next Spring’s Soil This Fall

It is never too late to put Biochar to work.

Add organic material

Sprinkle Biochar evenly

Repeat the layers

Keep it moist and aerated

Let biology do the work

You Still Have Time.

The Slow, Effective Charge

The faster charge

Biochar Is Not Just a Spring Soil Amendment

Build next season’s soil

Manage organic materials

Prepare the root zone

Help inputs work harder

From the Barn to the Compost Pile

What Does the Research Say?

Biochar for Every Scale of Composting

Fine Biochar

Coarse Biochar

Compost & Soil Prep

Commercial Biochar

Three Practical Starting Points

Biochar Is Powerful—But Not One-Size-Fits-All

Biochar & Compost FAQ

Your Best Spring Soil Can Start This Fall.

Talk to a Biochar specialist.

Made in British Columbia.Ready for your project.

How can we help?

See what Silvachar is doing.

Made in British Columbia.
Ready for your project.