I created a Christmas jumper I can wear every season

Matilda Welin sets herself the task of creating an affordable, environmental and long-lasting Christmas jumper, choosing recycled materials over fast fashion.

Christmas jumpers are fun. But they are also ugly, bulky and unpractical. Who thought synthetic knitwear was the best option when mingling in a sweaty crowd next to live candles? They're unsustainable, too, with up to 95% containing cheap plastic materials.

One in 10 people threw last year's Christmas jumper in the bin and almost two-thirds of 25-34-year-olds own more than one, according to research by Hubbub, an environmental non-profit in the UK, carried out in November. In 2019, Hubbub said it expected UK shoppers to buy 12 million new festive jumpers, despite already owning 65 million. This year, that number has risen to 69 million. It's not just a British phenomenon, either. In the US and Canada, the garments dubbed "ugly Christmas sweaters" are popular too, giving rise to charity walks and even trademarks.

Many organisations, including the non-profit Save the Children, which launched an annual Christmas Jumper Day back in 2012, now suggest that people take a normal jumper instead, and attach some temporary festive decorations. Mending and upcycling clothes is also growing in popularity more widely.

So when a friend invites me to her annual Christmas pub crawl, I tell her I'll be there in a jumper. I plan to take an abandoned sweater I already own and turn it into a home-made, environmentally friendly, affordable and long-lasting Christmas classic. How hard can it be?

First stop: my wardrobe. As I raid the shelves for some knitwear to transform, my gaze alights on a forlorn and slightly too small jumper of my partner's, three moth holes adorning the belly. It was probably going to end up thrown away, he says, granting me permission to use it. Moth holed and bound for the garbage heap – a double save! I feel very pleased with myself.

Next, I dig out a stack of unused fabric scraps and extra buttons from new clothes. I already own sewing tools, so my jumper ends up costing me nothing at all, but thread and needles can also be purchased new for less than £10 ($13). I decide that my favourite things about Christmas are music and the pine trees, and draw a sketch of a tree and some music bars to cut out in fabric and attach to my garment in a method known as appliqué.

A week passes. My smugness has disappeared – I have discovered that my jumper is made of 80% wool and 20% nylon. I call Meital Peleg Mizrachi, a researcher from the Yale Center for Business and the Environment and the Economic Growth Center at Yale University, for advice. While a 100% wool jumper is best for the environment and a 100% synthetic one comes second, she says, a mixed jumper, like mine, is arguably the worst, because the mixed materials are harder to separate for recycling. But the story doesn't end there. Material type, she says, is only one part of wearing sustainable clothes.

"The question that we need to ask ourselves is: 'What happens to all the clothes that we no longer want?'" says Peleg Mizrachi. They are bought, she explains, by traders in countries in Africa and Latin America, where torn or low-quality garments that can't be sold on further tend to end up in landfills or are incinerated. "In Accra, where the world's biggest second hand garment market is located, we see a lot of respiratory diseases and we see a lot of microplastics in the sea," she says.

I imagine sad, muddy Santa beards and green, sparkling "Ho ho ho!" letters poking out among huge rubbish mounds. In 2021, footage by France24 indeed showed piles of clothes including Christmas jumpers in the Chilean desert. The best way to stop this, Peleg Mizrachi says, is to wear your clothes more than once. Therefore, the material is arguably less important than how often I wear my jumper – after all, I already own it now. I could even create a garment I want to wear after Christmas, too, she suggests, maybe with parts I can remove. Behaviour, it seems, is the sustainability companion to material.

Next, I call Kate Hobson-Lloyd, a fashion ratings manager for the sustainable shopping app Good on You. One problem with Christmas clothes in general, she says, is that we are encouraged to buy new ones, in new designs and colours, every year. And while the Save the Children charity drive may have been a catalyst for the jumpers' popularity in the UK, she believes social media is to blame too.

"For example, when I Googled 'Christmas jumpers', there were quite a few that I saw that spoke about things like 'my Christmas era', focusing on the Taylor Swift Eras tour," she says. "You have to think: 'Is that going to work next year?'" The best thing to do, she says, is to go for longer-term trends. With my homemade jumper, she suggests, I can get around the problem by adding and switching stuff around.

Finally, I speak to Sarah Gray, lead analyst for textiles at the UK environmental non-profit Wrap. In a woollen garment, she says, the nylon is often there to improve durability. That means my jumper may last longer because of it. She doesn't worry too much about the scrap fabrics I will use to decorate, either.

"The main thing is to decorate [the jumper] in a way that you really like," she says. "Choose something that will make you happy... That feeling that you've got a garment that you like wearing, that's one of the top things to achieve."

Buoyed, I cut out notes in felt and attach them to a pair of old shoelaces to go between bars of music. They will cover some of the moth holes and an unsightly stitched-in brand on my jumper's chest.

When it comes to festive jumpers, I think to myself, re-wearing seems to be the gold standard – the longer a life the jumper has, the better. I decide to transform the appliqué into removable decorations, held in place by buttons, so that I can create new ones and swap them in when I want to.

When it comes to the designs on jumpers, electronics and flashing bulbs are problematic, Hobson-Lloyd tells me, because they can be hard to extract. In general, jumpers with the design knitted into the fabric rather than attached as 3D decorations on top are more sustainable and durable, she adds.

Next, I consider the environmental quality of the decorations. I am re-using plastic beads from an old necklace, and I always save scrap fabrics I like the look of from torn clothes, old tablecloths and sheets. The fabric for this project, though, is some old, shop-bought felt. To see what it is made of, I perform a burn test, setting fire to a corner of the fabric to see how it burns, and scrunch and cut the material a bit. The answer is unequivocal – it's synthetic. My heart sinks before I remember that I already own it and should use it then buy better next time. With the buttons, I can also remove the decorations before washing the jumper, to try to avoid potential polymers leaking from the material during a wash.

It may actually be best to spot clean synthetic jumpers rather than wash them, Hobson-Lloyd says, using things like alcohol-based sprays to get rid of smells. This is also good for jumpers with embedded electronics which risk being destroyed by water and which are otherwise effectively single-use, she says.

The music bars are wonky. I start again, with thread instead of shoelaces. It takes an hour to thread the needle with the thick woolly yarn. Time passes without me noticing.

On the morning of the pub crawl, I play Christmas songs on the stereo as I attach baubles to the felt tree and decorate the cutouts with green and yellow thread. Then, the jumper is done. I am so pleased with it! I leave for the pub crawl in a pale afternoon light, meeting my friends to chat, eat and be merry. The jumper holds up well, except for one set of Christmas baubles which fall off and I later reattach.

Time to go home to my family for Christmas. When I return, the new year will begin and I'll be wearing other outfits. As I place my old-new garment in the wardrobe, I ponder the hard work that goes into upcycling – and the resulting pride. I remember something Peleg Mizrachi told me before I started to sew: "If we already created something that is special and that will have a lot of memories, something we did with our own hand, then why throw it away after one time? Make it into something that remains year after year after year, and it really becomes special."

Next year, I'll certainly be wearing my jumper again.

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