Can you compost cotton?

  • Date: May 14, 2022

Cotton is a widely used material. From bed sheets to make-up removal products, you’ll find cotton in every room in your house. It’s properties – durability, breathability, softness and absorbency – make it a popular material for many different uses despite its lack of green credentials. With composting becoming a more and more popular way of dealing with household waste, it begs the question – is cotton compostable? Yes and no!

(If you are a composting novice, have a quick look at some of our start-up composting questions answered here! If not, read on…)

Is cotton biodegradable?

Cotton is biodegradable – microbes, such as bacteria, break it down naturally. In terms of biodegradability, it is pretty quick taking about 5 months to do so – and organic cotton breaks down even quicker.

Is cotton compostable?

Not everything that is biodegradable is compostable. To be compostable, an item must be able to aid the production of a nutrient-rich compost. Luckily, cotton can contribute to this – so the good new is that it can be popped in the compost pile.

However, this does not mean that you can throw all items with a cotton element in there. Unfortunately, not all cotton items are created equally when it comes to composting…

Is cotton wool compostable?

Sometimes yes, sometimes no. It depends on two main factors – is the cotton wool/cotton pad made from 100% cotton? And what have you used it for – does it contain any contaminants?

The cotton in these products is often coated with a synthetic material. This is usually to ensure they maintain their structure or to make them less fluffy (primarily in medical products – you don’t want strands of cotton in your wound). If the cotton wool is combined with a synthetic material, it is not fully compostable – the cotton wool element will biodegrade but the synthetic material will either not breakdown at all, or small pieces of it will be distributed throughout your compost. Although bigger pieces can be fished out, some pieces may break up and not be noticed – not ideal for your final compost.

If your cotton wool/cotton pad is pure cotton, you also have to be mindful of what product is on it – if you have used them for cosmetic purposes, they might contain chemicals that will contaminate your compost pile.

Is cotton clothing compostable?

Cotton is a great material for clothing. It is soft yet durable and also breathable. It is used in a variety of clothes from simple t shirts to jeans. As with other natural fibers, such as wool and silk, cotton can be composted. However, check the label – for it to biodegrade it must not be blended with any synthetic materials such as nylon or polyester.

If it is pure cotton, or a blend with another natural fiber such as wool or bamboo, it can go on the compost heap. First, make sure that that any non-biodegradable items such as zips and plastic buttons are removed then cut the items into small pieces. Unfortunately, even in pure cotton garments the thread may be made of polyester. This doesn’t mean you can’t compost it – just remove the threads from the compost at the end.

As for the items that contain synthetic materials, if in a reasonable condition perhaps you could donate them to a charity shop or list them on eBay? If not, there are lots of other ways to re-use them – from cloths for household cleaning to the stuffing in cushions, there are plenty options. Either way, the aim here should be to divert the items from landfill – composting is only one of many ways to do this.

Can I compost my cotton underwear?

If you have pure cotton undies these are fully compostable – however, before you through them in the compost pile ensure that you have cut off any elasticated waistband or boxer buttons. Although not strictly necessary, the composting process will be quicker if you cut the underwear into smaller pieces.

Like the other items, your underwear may not be pure cotton. Some have other synthetic materials like polyester blended in – these are not compostable. If this is the case with yours, you can donate them to charity shops (I never thought you could either….) or if not in good enough condition, you can recycle them. Planet Aid are a wonderful organization that make this simpler – just pop your garments into one of their conveniently located yellow bins throughout the country.

Are bedding and bath towels compostable?

Cotton bed sheets are breathable and also extremely soft, making them a great choice for a restful night. Cotton is often blended with polyester. Although this is a budget-friendly alternative, it does bring its disadvantages – these sheets don’t absorb moisture as readily and the fabric lacks the breathability factor. And you’ve guessed it – due to its polyester content, polycotton sheets are not suitable to be composted!

Similarly, bathing towels can be made from pure cotton or cotton blends – typically polyester. Although these blended towels have their advantages (they dry more quickly and are cheaper), composting is not one of them!

The bottom line

There seems to be a theme running through all the cotton items discussed! Although, 100% cotton can be composted, all cotton products are not made of pure cotton – and those blended with synthetic fibers cannot be composted unfortunately. Try to buy products that are pure cotton if you want to use your waste items to help produce some nutrient-rich compost for your garden. Although these may be a little more expensive, you are effectively getting some compost free with every pure cotton item purchased!