One year after the City of Calgary’s green cart program was rolled out, officials say residents still have a few things to learn about the system.

More than 100 million kilograms of food and yard waste have been diverted from the landfill since the green bins were distributed in 2017, 30 percent more than original estimates.

All of that material that’s collected is transformed into compost that is sold to farms and landscapers or given away to community gardens and the public at annual giveaway events.

However, even though the system is reducing the amount of black cart garbage by 46 percent, officials say Calgarians can do more by being more conscientious about what they toss into the bin.

“We're still seeing some plastic bags coming in instead of certified compostable bags,” says Laura Hamilton, Calgary’s waste diversion specialist. “It can be challenging when you're out shopping because there's a lot of confusing messaging out there on products. So we are really focusing on making sure Calgarians know to look for those certified compostable symbols.”

She adds that the conditions at the city’s southeast composting facility are perfect for breaking down waste that you couldn’t in a backyard composter, for example, seafood shells.

“Some people are really surprised at that because it seems like it’s such a tough material and might be difficult to compost. In a backyard composter, you probably wouldn’t put your meat, bones, dairy or those type of things, but our process is a little bit different. We get higher temperatures so those materials are safe and can be composted here.”

The city says residents should make sure that all their yard waste is packed in paper bags or certified compostable bags that bear the proper symbols. Any bags that won’t fit inside the bin can be left next to it for pickup.

Pet waste can also be deposited in your green cart, provided it is inside a secure compostable bag.

For more information on what can go into your green cart and the composting facility itself, you can consult the city’s website.