A quarter of all our rubbish contains food waste that shouldn't be there, according to new figures.
That's despite 4 out of 5 Welsh households using food caddies.
To help solve this, a new campaign has been launched to help people reduce food waste and dispose of it correctly.
Angela Spiteri from WRAP Cymru says the problem isn't that people don't know where food waste is meant to go.
She said: "Most people know that food waste should never go in the rubbish bin, yet it's the most significant item in there.
"And the worrying thing is that 80% of that could have been eaten."
At one primary school in Cwmbran, they're trying to teach children the correct way.
Phoebe Lewis is a teacher at Blenheim Road Primary. She said starting early is the best way to get the message across.
Ms Lewis said: "It comes from basic recycling skills in school, so remembering that we're using the right bins for our paper and our food waste.
"So they actually did a project whereby they would take a photo of how much food waste was left at lunch time, and then obviously scraping it into the correct bins, and we weighed up then how much food waste was actually done.
"We really want them to not just learn it at school, but do it at home, independently, from a young age."
The Welsh Government want to recycle 70% of waste by 2025.
Broadcaster and chef Matthew Pritchard backs the campaign.
He said: "I'm a cook myself, and when I'm cooking in the kitchen, a lot of our general waste is full of food, and it shouldn't be. And it's edible. So don't put it in the bin, put it in the caddy and then we can turn that waste into green energy.
"It's good to give that message to the younger generation of what to do with their food scraps.
"But it's good to know Wales is currently number three in the world- we want to make it number one!"
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