• Blog

Composting for businesses

Food waste rotting in landfills is a major source of the UK’s methane emissions (a powerful greenhouse gas) and a major setback for the ‘Net Zero Emissions by 2050’ goal established by the UN.

Despite this, only 20% of food waste in the UK is recycled back into useful products, including the soil amendments generated from composting.

UK businesses are significant contributors of food waste, and the expectation for them to compost on-site or at least arrange for its collection is steadily increasing.

This article covers everything your business needs to know to jump-start its composting program. Let’s dive in!

Contents:

• What is composting?
• What wastes can be composted, and which ones can’t?
• Setting up composting in your business
• The benefits of business composting

What is composting?

Composting is the process of decomposing biodegradable organic waste, such as food scraps and garden clippings, into a nutrient-rich soil amendment called “compost” (or “humus”, which refers to its naturally occuring equivalent).

This natural process involves microorganisms breaking down the materials, resulting in “compost” that can improve soil health and fertility.

Unlike the environmentally harmful decomposition in landfills (e.g., rotting), composting emits significantly less carbon emissions because it occurs in the presence of air (i.e., an aerobic process).

Composting in waste management is essentially an adaptation of the natural process that occurs in grasslands and forests.

Microorganisms break down any available dead organic material in the search for nutrients, leaving behind a black, spongy “humus” that improves soil health and fertility.

💡 What does “biodegradable” mean? Any organic matter, including plastics, will eventually degrade into its original carbon molecules. However, only those that can be reasonably broken down within a short period, typically months to a few years, count as “biodegradable.”

What wastes can be composted, and which ones can’t?

Any biodegradable waste can theoretically be composted. However, depending on the specific composting methods, successful composting requires a prescribed combination of these waste ingredients.

Compostable waste

The following organic wastes can be composted under all circumstances:

💡 Wet cardboard: If your business is earning recycling rebates from cardboard recycling, it is inevitably generating low-quality or spoilt cardboard that it cannot sell. This cardboard (often wet or low quality) is a great addition to a compost heap used to rebalance when there are excess greens.

Non-compostable, biodegradable waste

The following wastes should only be composted in specific circumstances to avoid attracting pests, emitting foul odours, or adding pathogens or pollutants to the final “compost” mix. Here are some principal examples:

Setting up a business composting program

Setting up composting for your business has many benefits, including compliance, environment and employee well-being. Setting up composting is simple as long as you follow this step-by-step process:

1. Initial assessment.
2. Deciding on whether to compost on-site or outsource it.
3. Assessment and improvements

1. Initial assessment

This step involves understanding your business’s situation to implement the solution that best meets your needs.

This includes a waste audit, a cost-benefit analysis, and ultimately weighing up your options.

Waste audit

Measuring the weight and volume of your composable organics will help you calculate the size of your waste collection bin or the required size of your on-site composter.

Small-scale composting activities for small to medium businesses are typically exempt from special environmental and health and safety permits, but larger operations processing multiple tonnes of organic waste at any one time will require special permits.

Your mix of compostables is also crucial to assess whether its feasible to do this on-site or simply outsource.

Cost analysis

For a cost analysis, we recommend collection quotes from various food and garden waste collection companies and companies that can help you set up on-site composting.

2. On-site vs commercial composting

There are two composting routes any UK business can take:

1. Arranging the collection of all biodegradable organics (cardboard, food, garden).
2. On-site composting (or a mix of composting and collection).

Commercial composting (Outsourcing)

Commercial waste collection providers will pick up your waste and take it to either a licensed composting facility or a biofuel production facility, whichever is more convenient.

In the UK, approximately 272 permitted composting sites process around 6.8 million tonnes of food and garden waste annually from homes and businesses.

The resulting soild amendment is used in agriculture and landscaping, with about two-thirds sold off-site to users​. Here are two notable examples of commercial composting facilities in the UK:

New Earth Solution (Kent, England): This Kent waste management facility opened in 2013, and uses In-Vessel Composting (IVC), a method in which organic waste is decomposed in a controlled, enclosed environment. The facility handles approximately 60,000 tonnes of waste annually and produces PAS-100-certified compost.

Veolia’s Green Energy Plant (Southwark, London): This London waste management site uses Open Windrow Composting, a method best suited for processing garden waste. Organic materials are piled into long rows (windrows) and regularly turned to introduce oxygen and manage temperature. The Southwark plant processes around 20,000 tonnes of green waste annually and produces PAS-100-certified compost.

Unless your business handles hundreds of tonnes of food waste annually, it is recommended that you negotiate with a vetted commercial waste collection provider that operates in your local area.

On-site composting

Businesses of all sizes, settings, and circumstances can legally compost their organic waste on their premises without any additional permits as long as they are not composting animal by-products or large amounts of waste.

There are various methods to chose from:

Training and involvement

As simple as composting is (it requires a few minutes of monitoring per week), all on-site composting methods require training and some commitment. This is because the health of microorganisms and their environment needs monitoring to ensure it remains odourless and pest-free.

While each composting method has its intricacies, the following always holds:

• The compost must be well-aerated to avoid foul smells from anaerobic decomposition (i.e. rotting).
• The compost must be balanced 1:3 in terms of greens and browns.
• The compost must remain moist but not water-logged.
• Avoid adding troublesome biodegradable waste.

These are covered in more detail in our composting process section.

3. Assessment

Once you have established your composting method and gone through the process for a whole year (to control any seasonal variables), it is worth assessing:

• How much have you saved by composting?
• Are my employees interested?
• Have you seen any intangible benefits from composting?

These will help you identify areas for improvement and whether you should consider outsourcing your composting or, alternatively, starting it in-house.

The composting process

The composting process is vastly similar, whether its done at a business’s premises or outsourced to a private or municipal composting facility. The underlying natural process is the same: Microorganisms breaking organic matter down. Here is a summary:

1. Segregation
2. Preparation
3. Composting
4. Maturation and harvesting

Segregation of organic waste

Organic wastes such as kitchen scraps, garden and plant pot clippings, and other biodegradable items like spoilt cardboard are segregated and stored separately in compost bins prior to composting at the business premises.

See what biodegradable items you should and should not compost here.

Preparation for composting

While not all composting methods require reducing the raw organic waste in size by shredding, chopping or cutting, it is usually very beneficial to do so as it increases the surface area for decomposition.

To achieve a well-balanced compost, green (nitrogen-rich) and brown (carbon-rich) organics should be mixed as close as possible to its optimal decomposition ratio of 1:3 by volume:

Composting

While the composting process begins as soon as the organics become waste, it accelerates once incorporated into the composting vessel.

This could be forming the correct ratios into a layered pile for Windrow Composting or simply mixing them well before adding them to the Vermicompost, Bokashi or In-Vessel bins for composting.

While In-vessel and Bokashi composting is hands-off, moisture and aeration levels must be carefully managed in other methods.

The decomposition process will slow down if the compost pile or waste material is too dry, and if it is too wet, it will stink and potentially harbour pathogens.

Also, ensuring enough organic material is composted together is essential to raising its temperature. Your compost needs to maintain a temperature of at least 55C for several days to kill any introduced seedlings and many pathogens.

Maturation and harvesting

Once the active composting phase slows down, typically after a few weeks or months, the compost ‘cures’ and stabilises, ensuring any remaining organic matter fully decomposes.

The finished compost should be dark, crumbly, earthy-smelling and free of seedlings (if possible). The compost can enrich garden soil, improve plant health, and enhance overall soil structure.

The benefits of business composting

Starting a composting program at your business is hugely beneficial for your employees, waste management costs, and the environment, whether you arrange for its collection or do it on-site:

However, on-site composting programs that require more involvement from your staff have many other intangible benefits.

The added benefits of on-site composting

Composting on-site is more environmentally friendly because it avoids the added environmental impacts of waste transportation, including emissions.

Involving employees in the composting process is educational and team-building because it is a hands-on process in which very few, especially urban Britons, have little to no experience.

Also, you should expect employees to experience improved well-being from working “with nature” and pride from doing “the right thing.”

While these benefits are sometimes difficult to communicate to stakeholders or management because they are “intangible”, “soft”, or difficult to measure, you can be certain they’re a step in the right direction.

The environmental benefits of composting

Composting is arguably the waste management method with the clearest environmental benefit. Not only has it proven simple and doable at any scale, but it also prevents harmful methane emissions from landfills while producing fertile soil, a commodity in global decline.

The best thing, even small businesses like small offices, barbershops or corner shops can do it in-house and achieve:

Back to blog Back to water guides

• Share:
• 
• 
• 
•