Your Essential Composting Guide: What Belongs in Your Bin and What Doesn’t?

Your Essential Composting Guide: What Belongs in Your Bin and What Doesn’t?

In this simple guide, we'll explore everyday items suitable for your compost bin, sourced from both your kitchen and garden.

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Welcome to the world of composting! In this simple guide, we'll explore everyday items suitable for your compost bin, sourced from both your kitchen and garden. We'll also cover what items to steer clear of, ensuring you turn ordinary waste into a nutrient-rich boost for your garden. Ready to unlock the magic of composting? Let's get started!


What Can I Compost? 5 Kitchen Items for Your Compost Bin

These kitchen items in your compost bin can provide various benefits, as they contribute to creating nutrient-rich compost for your garden. Here are the benefits of putting these items in the compost bin:


Fruit and Vegetable Peels

Nutrient-Rich Compost: Fruit and vegetable peels are rich in organic matter and essential nutrients. Including them in your compost bin adds valuable nitrogen and other micronutrients to the compost, promoting healthy plant growth.


Loose Leaf Tea/Paper Tea Bags

Compost Aeration: Loose leaf tea and paper tea bags contribute to aeration in the compost pile. They help create air pockets, allowing better circulation and preventing the compost from becoming too compacted. Good aeration is essential for the composting process.


Stale Bread and Cooked Plain Pasta

Carbon-Rich Material: Stale bread, like pasta, is a source of carbon. It adds bulk to the compost, helping to maintain the carbon-to-nitrogen balance. Breaking the bread into smaller pieces before composting can accelerate its decomposition. Small quantities of plain pasta can enhance the diversity of organic matter in the compost.



Calcium Enrichment: Eggshells add calcium to the compost, which is an essential nutrient for plant development. Calcium helps prevent issues like blossom end rot in tomatoes and peppers. Crushed eggshells also aid in improving the structure of the compost.


Coffee Grounds

Nitrogen Boost: Coffee grounds are a nitrogen-rich material that adds valuable nutrients to the compost. They also enhance the microbial activity in the compost pile. Coffee grounds are particularly beneficial when mixed with carbon-rich materials like leaves or straw to maintain a balanced compost.


What Can’t I Compost? 5 Kitchen Items to Leave Out of Your Compost Bin

While composting is an excellent way to recycle kitchen waste, some items are best avoided in the compost bin due to potential disadvantages or challenges.


Citrus Fruit Peels

Slow Decomposition: Citrus peels, such as those from oranges and lemons, contain natural oils and compounds that can be slow to decompose. They may take longer than other compostable materials, potentially slowing down the overall composting process.


Onion and Garlic Scraps

Odour Concerns: Onion and garlic scraps can contribute strong odours to the compost. While they are compostable, some people avoid them to prevent attracting pests or producing unpleasant smells in the compost pile.


Meat, Fish, and Bones

Risk of Pests and Odours: Meat, fish, and bones can attract pests like rodents and may produce strong odours as they decompose. Additionally, the decomposition of these materials can take longer and requires higher temperatures to break down effectively.


Dairy Products

Odour and Pest Issues: Dairy products, such as milk, cheese, or yogurt, can lead to unpleasant odours in the compost pile and attract pests. The decomposition of dairy can also be slow and may result in a slimy texture in the compost.


Stickers on Fruit and Vegetables

Contamination: Stickers on fruits and vegetables often have adhesive and may be made of materials that don't compost well. If these stickers end up in the compost, they can contribute to contamination. It's best to remove stickers before adding produce scraps to the compost bin.


What Can I Compost? 5 Garden Items for Your Compost Bin

Including these garden items in your compost bin can provide numerous benefits, as they contribute to creating a well-balanced and nutrient-rich compost for your garden. Here are the benefits of putting these items in the compost bin.


Chopped Up Twigs and Small Branches

Aeration and Structure: Twigs and small branches add structure to the compost pile, promoting better aeration. They create air pockets that allow oxygen to reach the microorganisms responsible for decomposition. Improved aeration helps prevent the compost from becoming too compacted.


Fall Leaves and Pinecones

Carbon-Rich Material: Fall leaves and pinecones are excellent sources of carbon, balancing the nitrogen-rich kitchen scraps in the compost. The carbon-nitrogen balance is crucial for efficient decomposition. Fall leaves also add valuable minerals to the compost, enriching it with nutrients.

Fall leaves in a wheelbarrow



Carbon Source and Moisture Retention: Woodchips are another carbon-rich material that contributes to the carbon-nitrogen balance. They help maintain proper moisture levels in the compost pile by preventing excessive water evaporation. Additionally, woodchips break down gradually, providing a slow-release carbon source.


House Plant Trimmings

Diverse Organic Matter: Trimmings from house plants add a variety of organic materials to the compost. Including different types of plant material ensures a diverse mix of nutrients in the compost. It also prevents the compost from becoming too homogeneous, promoting a healthier microbial community.


Grass Clippings

Nitrogen-Rich Material: Grass clippings are a valuable source of nitrogen, helping to balance the carbon from woody materials in the compost pile. The nitrogen in grass clippings accelerates the decomposition process and promotes the development of rich, fertile compost.


What Can’t I Compost? 5 Garden Items to Leave Out of Your Compost Bin

While composting is an excellent way to recycle garden waste, there are certain items that are best avoided in the compost bin due to potential disadvantages or challenges.



Risk of Regrowth: Tomato seeds have the potential to survive the composting process and may sprout in your garden when you use the finished compost. This can lead to unwanted tomato plants growing where you don't want them. To prevent this, it's advisable to discard tomato plants or fruits in the regular waste bin.


Naturally Toxic Plants

Potential Harmful Compounds: Some plants contain natural toxins or chemicals that may persist in the compost and affect the quality of the finished product. Examples include certain types of toxic or invasive plants. It's best to avoid composting these plants to prevent potential harm to your garden or soil.


Large Branches or Treated Wood

Slow Decomposition and Contamination: Large branches take a long time to decompose fully, and treated wood may contain chemicals that are not suitable for composting. Additionally, the decomposition of large woody materials can result in a carbon-to-nitrogen imbalance and slow down the composting process. It's recommended to use a woodchipper or find alternative ways to recycle or dispose of large branches.


Diseased or Infected Plants

Risk of Disease Spread: Composting diseased or infected plants can potentially spread diseases to the finished compost. Certain plant diseases may not be eliminated during the composting process, and using the compost in your garden could introduce or exacerbate disease issues. It's safer to dispose of diseased plants through other means.


Grass Clippings Treated with Pesticides

Chemical Residue Concerns: Grass clippings treated with pesticides can contain chemical residues that may persist in the compost. These residues can potentially harm beneficial microbes and insects in the composting process. To avoid introducing harmful chemicals to your compost, it is best to compost untreated grass clippings or those from pesticide-free lawns.


Crafting the Perfect Compost Mix: A Recipe for Success

As seen above achieving a well-balanced compost is crucial for optimal plant growth and soil health. So why is a mixture of all these necessary to making a well-rounded compost pile?

  • A balanced mixture of nitrogen-rich (green) and carbon-rich (brown) materials ensures a nutrient-rich compost, supporting plant development.
  • Adequate compost aeration promotes the activity of beneficial microorganisms, preventing unpleasant odours and facilitating efficient decomposition.
  • Carbon-rich materials contribute to moisture retention, crucial for microbial activity, and slow-release nutrients from items like nutshells enhance the compost's long-term fertility.
  • Diverse organic matter enriches the nutrient profile, catering to a range of plant needs, while carbon sources with structure, like straw or wood chips, maintain proper aeration for a healthier compost pile.

This holistic approach results in a nutrient-dense and well-structured compost that enhances soil fertility and plant resilience in the garden.


When Should I Start Composting: Seasons and Considerations

Composting can be done throughout the year, with different seasons offering advantages and considerations. Spring and fall are generally optimal due to moderate temperatures and a balanced mix of green and brown materials, while summer provides warmth for accelerated decomposition. Composting in winter is possible, though the process may slow in colder climates.


Maturing Compost: Patience Rewarded

The time required for compost to mature varies depending on the composting method and environmental factors. In hot composting, where the pile is actively turned and maintained at high temperatures, finished compost can be produced in as little as 4 to 8 weeks. Environmental conditions, including temperature and moisture levels, also influence the speed of decomposition.


Smart Storage for Happy Compost

For effective compost storage, use airtight containers with a damp cloth on top to retain moisture. Keep it in a cool, dry place with ventilation, avoiding airtight plastic bags. Label containers with the compost batch date, and check and adjust moisture levels periodically. If space is limited, freezing compost in airtight bags can help preserve nutrients. These practices ensure stored compost remains viable for garden use.

Achieving a well-balanced compost mix is emphasised for optimal plant growth to ensure your garden flourishes year-round. Composting is presented as a year-round endeavour that not only reduces waste but also contributes to a healthier, more resilient garden over time.

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