| Garden Waste | Will It Decay | Cold | Hot | HOTBIN decay rate | Comments |
| Accelerator Powders | Yes | Yes | Yes | Fast | We do not recommend adding these into the HOTBIN. |
| Alfalfa | Yes | Yes | Yes | Medium | |
| Autumn Leaves | Yes | Yes | Yes | Slow | Can be hard to break down - we recommend adding dried and roughly shredded autumn leaves in small handfuls each week. |
| Bird Feathers | Yes | Yes | Yes | Slow | |
| Bone Meal/ Blood Meal | Yes | Yes | Yes | Fast | These can help speed up composting. |
| Branches | Yes | Yes | Yes | Very slow | The larger the branches, the slower they are to compost. You really should shred or chip. |
| Coir - Coconut Husk Fibre | Yes | Yes | Yes | Very slow | Takes a long time, but the fibres do mix in. |
| Conkers | Yes | Yes | Yes | Very Slow | Protective shell will take longer to compost. Chopping or smashing them up will help to compost more efficiently. |
| Couch Grass | Yes | Not Advised | Yes | Medium | Should only be added once the HOTBIN has reached 60°c to ensure that all of it is composted effectively. |
| Diseased Plants | Yes | Not Advised | Yes | Medium | High temperatures kill disease virus/bacteria. |
| Deep Rooted Weeds - Dandelion, Ground Elder Etc | Yes | Not Advised | Yes | Medium | |
| Fertiliser - Ammonium Sulphate | No | Yes | Yes | Fast | Limited value & high cost. |
| Flowers - Stems, Dead Heads, Roots | Yes | Yes | Yes | Medium | |
| Shell of Garden Snails | Yes | Yes | Yes | Very slow | Speed up composting by crushing the shells - please check they are empty first! |
| Grass | Yes | Yes | Yes | Medium | Grass is a large volume waste. It can be tricky to compost quickly in a cold compost bin. We recommend drying the grass out slightly to prevent excess water from entering the HOTBIN. |
| Grass Sods | Yes/No | Yes | No | Medium | Adding these will only block airflow through the HOTBIN. Only the grass composts. |
| Grass With Weed Killer On It | Yes | Yes | Yes | Medium | Domestic weed killers are biodegradable - please check individual product instructions. |
| Green Leaves | Yes | Yes | Yes | Medium | Shred waxy leaves. |
| Ground Cover - Nettles | Yes | Yes | Yes | Medium | |
| Hay | Yes | Yes | Yes | Medium | |
| Herbicides | Yes | Not Advised | Yes | Medium | Domestic herbicides are biodegradable - please check individual product instructions. |
| Hydrogels - SAP, PAM | Yes | Not Advised | Yes | Slow | Can also be added to soil. |
| Japanese Knotweed | Yes | Not Advised | Not Advised | Medium | |
| Leylandii Conifer | Yes | Yes | Yes | Slow | Ensure these are well shredded or chopped and add in small amounts rather than a single layer. |
| Lime - Calcium Carbonate | No | Not Advised | Not Advised | - | Lime is not biodegradable. It also affects the pH levels and can stop the composting action so is best left out. |
| Moss | Yes | Yes | Yes | Slow | Takes ages - it is best added in small amounts each week. |
| Old Compost | Yes | Yes | Yes | Slow | Acts as a fantastic kick starter! But do not add too much. |
| Other Non-Native Weeds | Yes | Not Advised | Yes | Medium | |
| Perlite | No | Not Advised | Not Advised | - | |
| Pesticides | Yes | Not Advised | Yes | Medium | Domestic pesticides are biodegradable - please check individual product instructions. |
| Pine Cones and Pine Needles | Yes | Yes | Yes | Slow | |
| Plants With Fungus On | Yes | Not Advised | Yes | Medium | High temperatures should kill the fungi. |
| Prunings | Yes | Yes | Yes | Slow | Shred or chop where possible. |
| Ragwort | Yes | Not Advised | Yes | Medium | Should only be added once the HOTBIN has reached 60°c. |
| Rock /Volcanic Dust | No | Not Advised | Not Advised | - | We question the reason for adding small rock particles to compost. |
| Rhubarb Stems & Leaves | Yes | Yes | Yes | Medium | |
| Seaweed | Yes | Yes | Yes | Medium | Ensure the salt is rinsed off. Seaweed is thought to encourage other materials to break down more quickly. |
| Soil | No | Not Advised | Not Advised | - | It seems counter-intuitive not to add soil however, try not to! Large sods and/or thick layers prevent aeration and could cause your HOTBIN to become anaerobic. You only need to use a small handful to inoculate a new heap. |
| Slugs & Snails | Yes | Yes | Yes | Medium (shells - slow) | Kinder to add once dead - the high temperatures would kill them. |
| Straw | Yes | Yes | Yes | Medium | |
| Twigs & Brambles | Yes | Yes | Yes | Slow | |
| Vermiculite | No | Yes | Yes | - | Can add to soil. |
| Weeds - Convolvulus, Dandelion, Bindweed, Buttercup & Horse Tail | Yes | Not Advised | Yes | Medium | Safer to compost in a hot composting bin - as the seeds are likely to survive cold composting. |
| Waxy Leaves - Ivy, Laurel, Holly | Yes | Yes | Yes | Slow | Shred or chop these before adding. Do not add in thick layer and mix in well. |
| Worms | Yes | Yes | Yes | - | |
