We drink a lot of tea.
The British drink 36 billion cups of tea a year, while in 2018 the US consumed 84 billion cups.
Almost all of that is in the form of tea bags rather than loose tea.
So it makes sense to do something useful with leftover tea – something like composting.
After all, a single teabag might not make much compost, but a year’s worth of teabags from a family can.
Leftover tea itself is very compostable. Tea is generally considered high in nitrogen, one of the key ingredients plants need.
Tea also consists of small particles, which means compost bacteria have got more surface area to work on.
Nutrient levels in tea leaves
There are various levels of nutrients reported for tea leaves.
One Guardian article reports them as follows:
- Nitrogen: 4.4%
- Phosphorus: 0.24%
- Potassium: 0.25%
(4.4% nitrogen doesn’t sound like much, but is in fact high – higher than all fresh manures.)
Unfortunately, I haven’t been unable to find the source data for the nutrient levels.
What I have found is different levels of nutrients, so treat the above table with caution!
What’s the problem with tea bags?
However, most people drink tea in the form of tea bags, avoiding traditional teapots and reusable tea bags.
You can compost some tea bags, but if you are worried about small amounts of plastic, you won’t be able to compost all tea bags.
That’s because many tea bags do contain plastic.
One study found that a single tea bag could release 11.6 billion microplastics and 3.1 billion nano plastics.
Alarmingly, that’s just the plastic released into the water you drink, not the actual compost!
If you’re keen to eliminate microplastic from your soil, homegrown veg and local environment, you’re best off not using those tea bags.
Fortunately, tea retailers are increasingly aware of composters’ needs and their impact on the environment, and many are now changing the design of their tea bags
But plans don’t always come to fruition, as some companies haven’t mastered the art of creating tea bags without using plastic.
For example, when Yorkshire tea first tried to create compostable tea bags, their bags fell apart in people’s cups.
As we shall see, even when tea bags use plant-based plastics, they won’t always break down in home composting systems.
Does it really matter if compost contains tiny amounts of plastic?
Let’s face it, much of the food we buy in the shop comes from soil with plastic in it.
A lot of commercial compost is produced from household waste, and not all households are 100% vigilant when it comes to keeping out every little bit of plastic.
The situation is bad enough that at one conference, Kathy Nicholls of the UK environment agency threatened a crackdown on composting sites.
As home gardeners and compost creators, we can go one better than commercial suppliers.
After all, one compelling reason for creating our own compost and growing our own food is to get better soil, and healthier vegetables – and do our little bit for the environment.
It’s true that scientists say we need to do more research to know the full effect of plastic in the soil, and how bad it is for us.
But what we do know is that these plastics contain pollutants such as DDT, can have negative effects on soil life (including worm fertility), and can move up the food chain.
So while there may not be much plastic in tea bags, in an ideal world we’d avoid it.
Oil-based plastic v. plant-based plastic
It does get slightly more complicated.
Some companies use oil-based plastics, which are not advised for use in compost.
However, other tea companies, such as Clipper, used plant-based plastics (PLAs), and even claim that these are not plastic.
As Yorkshire Tea discusses more frankly, while PLAs are plant-based, they are still plastic.
What’s more, while they do seem to break down quite readily in industrial composting systems, they often don’t break down in home composting systems.
This may be because of the lower heat (and the reduced amount of time compost is hot) in home systems compared to industrial composting.
Green SXM states that some types of plant-based plastics should start degrading at between 111 and 140 degrees Fahrenheit (44 – 60 celsius).
That’s perfectly achievable if you have a well-constructed compost heap/pile, but probably not realistic at the temperature most people get to at home.
Which tea bag brands are compostable (or, at least, don’t contain traditional plastic)?
There are a number of brands that have eliminated all oil-based plastic from their bags.
- Abel & Cole Clipper
- Co-op own brand 99
- Pukka Herbs Teapigs
- Twinings pyramid range
- Waitrose Duchy range
- Tesco own brand
- Yorkshire tea bags (a change from when we first wrote this article)
- Aldi own-brand tea bags
- Red Label and Taste the Difference caffeinated
- Waitrose own-brand caffeinated bags
- Tetley Original
- M&S own-brand tea bags
Which tea bags contain no plastic?
- Hampstead Tea bags (with the exception of Earl Gray and Jasmine Tea).
- Neal’s Yard Biodegradable bags.
- Pukka Tea Biodegradable bags.
- Dilmah Organic.
- Harney & Sons.
- Higher Living Teas.
- Lipton – Quality Black and Intense traditional tea bags.
- Lyons (40, 80 and 160 packs)
- Nature’s Cuppa Organic
- Qi Tea
In summary, tea leaves are great for composting, but tea bags may not be so good.
Many companies are going to great lengths to switch to plant-based tea bags. However, these may not break down well in home compost systems – especially systems that do not get very hot.
If you are worried, simply snip the tea bags open and empty the bag into your kitchen caddy.
Alternatively, simply switch to loose-leaf tea and/or reusable tea bags!
Squeeze the tea bags before adding them to the compost. Tea bags are very wet – and often combined with other wet materials – so this helps reduce moisture levels.
As we’ve seen, tea is very high in nitrogen. As always, it’s important to balance high nitrogen (green) materials with high carbon (brown) materials, such as some shredded newspaper. Absorbent brown materials can also help absorb any excess moisture and provide air pockets in the compost.
If you are concerned about the plastic in tea bags, simply snip or tear the bag open and tip out the tea leaves.
You can simply remove the bags by hand or sieve them out. There is still uncertainty over how long they take to decompose when they are not composted, so it is best to add them to your recycling, or a compost collection where the bags will be taken to an industrial composting facility.
You can compost cardboard, carton board or paper wrapping. Anything with plastic or foil should be avoided.