How Halloween’s pumpkin obsession became an environmental nightmare – A greener life, a greener world

By Anders Lorenzen

In the lead up to Halloween, we are putting a spotlight on the environmental and climate consequences of the growing Halloween contributed pumpkin consumption.

What was once almost exclusively a North American tradition is now a global phenomenon, thanks to globalisation and the Americanisation of many societies — and with that come environmental consequences.

Like many European countries, the UK has embraced Halloween with enthusiasm — but also with rising environmental costs.

The scale of the Halloween pumpkin craze

Every October, supermarket aisles fill with crates of bright orange pumpkins — and millions are bought, carved, and discarded within days. 

In 2024, UK households purchased an estimated 40 million pumpkins, and according to the environmental charity Hubbub, more than half were thrown away uneaten. That’s over 20,000 tonnes of edible food — the equivalent of 95 million meals, enough to feed the UK’s entire population for almost two days.

Escalating pumpkin consumption and waste, in conjunction, cause environmental, water, and climate impacts, with huge greenhouse gas (GHG) and water footprint issues.

How pumpkins became a waste problem

Originally grown for eating, most pumpkins sold in the UK today are bred for carving. They are large, watery, and bland compared to smaller culinary varieties. 

Shoppers often don’t realise they’re edible; few use the flesh or seeds. Once carved, pumpkins spoil quickly — especially if left outdoors or under candlelight — making them unsuitable for later cooking.

Breaking down the climate and environmental costs of pumpkin consumption and waste

Growing pumpkins has a significant water footprint, with the UK charity WRAP estimating that the UK’s water footprint equates to 2 billion litres.

The relatively small size of the UK pumpkin-growing industry means that to meet demand, many must be imported from France and Spain, which adds to travel emissions and plastic packaging waste. 

The carbon and water footprint of pumpkins explained

Including the usage of fertiliser and on-farm emissions, a verified footprint for winter squash (pumpkin) grown in open fields in the UK is about 0.27 kg CO₂e per kg.

A typical 3 kg pumpkin has an on-farm footprint of around 0.8 kg CO₂e, similar to driving a small petrol car for nearly 3 miles.

Water use is also significant: growing a single 3 kg pumpkin requires up to 1,000 litres — roughly 10 bathtubs of water.

Post-consumption impacts 

The problem extends beyond the bin. If discarded into landfill sites, the pumpkin’s GHG footprint will increase, as methane emissions will be released. Methane is a short-lived greenhouse gas, but around 28 times as potent as CO2. 

Other European countries face similar challenges. Seasonal surges in ornamental pumpkin sales occur in France and Germany, while food waste activists push for better labelling and public awareness.

Advocates push for a more responsible pumpkin consumption

Experts and campaigners are urging a less wasteful and more usable approach. The flesh and seeds on the majority of carved pumpkins are edible. When carving, consumers are encouraged to save flesh for soups, curries, and baked goods such as muffins, roast seeds for snacks, or blend into pesto. Even if you’re not going to use it straight away, pumpkin puree can be frozen for months for later use.

In cases where pumpkins cannot be eaten or are not possible, the second-best option is to compost them rather than send them to landfills. Some local authorities even offer pumpkin collections.

Consumers are also urged to shop smarter and choose culinary pumpkin varieties over carving varieties. This offers the best use cases, supports local farmers, and cuts transport emissions.

Finally, pumpkins offer various other post-Halloween life use cases, using shells as candle holders or planters.

Refocused pumpling awareness

With Halloween 2025 fast approaching, local councils and campaigners are urging consumers to rethink the season’s rituals — carving less, cooking more, and ensuring no pumpkin ends up haunting the landfill.

In our next Halloween article, we will unveil a recipe that will give you ideas for using leftover pumpkin and a simple treat.

In 2025, Halloween is held on the 31st of October across the globe.

Anders Lorenzen is the founding Editor of A greener life, a greener world.