Composting has incredible benefits, from adding nutrient-rich soil to your garden to reducing food and yard waste from entering the landfill. And thankfully, the eco-conscious city of Portland makes composting quite easy for residents, from providing food and yard waste pickup to offering resources for creating your own backyard composting system.
Get started with your natural garden recycling journey using our composting guide, filled with general information about composting, local resources and more. The compost you create will benefit both your garden and the planet!
Compost is described as “organic material that can be added to soil to help plants grow” by the EPA. It is composed of four basic ingredients: browns, greens, air and water. Browns include materials such as dead leaves, branches, twigs and all other “woody” materials, which are high in carbon. Greens include materials like grass clippings, vegetable waste, food scraps and coffee grounds, which are high in nitrogen. The ratio of browns to greens should be 30:1 for the proper breakdown of materials, so it’s important to put in much more brown materials than green.
There are several methods to composting, from getting your compostable materials hauled off your property to composting them yourself in a pile or a bin that you either build or make yourself.
For an extra low-maintenance approach, you can place fall leaves and small garden clippings (6 inches or shorter) in a pile you cover in the winter and keep moist in the summer. This will break down in about a year. For larger woody materials and fruit and vegetable trimmings, you will need to be a bit more active with turning and monitoring the pile, and they take a little longer to break down.
The best and easiest way to layer compost in your bin or pile is by doing a lasagna layering method, which doesn’t require turning and prevents pests from accessing food scraps. Essentially, you are creating an external barrier of browns with greens located in the center of the pile, with substantial layers of brown layers between the greens. Click here for a visual of this method and here for a guide to lasagna composting from Oregon State University.
What Can Be Composted
Just about anything that was once living, including yard waste and animal products, can be added to the compost bin. Plus, there are several types of food and paper products that make excellent compost.
All types of food are compostable, including meat, poultry, fish, shellfish, bones, eggs and eggshells, cheese, dairy, bread, baked goods, pasta, rice, beans, nuts, seeds, vegetables and fruit, peels, and pits. Plus, raw or cooked food, table scraps, plate scrapings, leftovers, and spoiled food can be composted as well.
Yard debris, such as weeds, leaves, vines, grass, small branches, flowers, house plants, plant clippings, fallen tree fruit and pumpkins, can be composted.
You may also compost coffee filters, tea bags, paper napkins, paper towels and pizza delivery boxes — just be sure to remove any plastic or wax paper.
What Cannot Be Composted
There are several things that cannot be composted, as they will not break down. This includes: waxed paper, parchment paper, facial tissue, coffee cups, paper plates, take-out food containers or wrappers, drink cups, straws, or utensils — even if they are labeled as “compostable,” “biodegradable,” or “made from plants.” Plus, pet waste, animal bedding (including straw and chicken manure), animal carcasses from hunting, and fishing waste cannot be composted. Also keep fireplace ashes, dirt, rocks, sod, lumber, treated wood, sawdust, stumps or large branches (more than 4 inches thick or 36 inches long) out of the compost bin.
Have Your Own Backyard Compost Bin
Reap the benefits of completed compost by having your very own compost bin in your backyard. There are several sizes, types and styles to choose from, whether you’re in a smaller space with a balcony or have plenty of land to spare. Metro sells compost bins by EnviroWorld, which are great for beginners and smaller yards and feature a rodent-resistant floor and a door at the base for easy collection of finished compost. MetroPaint’s Swan Island store has everything you need to get started composting today, including these bins and other supplies, like a compost aerator and a kitchen compost container.
If you’re feeling crafty, you might make your own compost bin using this guide from Metro. Using wood and wire, you can create either a single bin or a three-bin system for turning and aging compost at different rates.
Get Yard + Food Waste Picked Up
If you’d rather not maintain a compost bin in your yard, you can easily have your food and yard waste picked up on a weekly basis. Portland residents with regular disposal service will be provided with a green 60-gallon “Portland Composts!” roll cart for collecting your compostable materials. Simply place your cart at the curb by 6 a.m. on collection day, making sure to not obstruct the container from view or place them in a difficult place to access. Pickup is free but additional costs are incurred for extra cans, bags or bundles. Click here for more details about compost collection in the city, including instructions, restrictions and weight limits.
Kitchen Compost Containers + Approved Liners
The easiest way to collect food scraps is by putting them in a small container that lives in your kitchen, so you don’t have to lug them out to the compost bin day after day. Just about any container with a lid works for collecting food scraps, but choose one with a carbon filter to reduce odors. We love this stylish Bamboo Compost Bin made by Bamboozle!
You can also add an optional liner to your kitchen compost container to keep it clean and make the transfer much smoother. NOTE: The City only accepts compostable bags from the following brands:
Your compost should be as moist as a wrung-out sponge — pretty moist but not soggy or soaking wet. If you have a layer of browns protecting the pile at all times, this should eliminate too much moisture from saturating your pile. Maintaining the 30:1 ratio is important for moisture control! Keep compost piles away from direct sun and areas where rainwater collects.
Whether you’re a seasoned composter or a newbie, you may come across some issues in your composting journey — and that’s okay! It’s all a part of the process and you’ll get the hang of it as the seasons go on. Oregon Metro put together a list of common composting issues with some recommendations for success.
Purchase Finished Compost
If you want to take advantage of the city’s high-quality compost (whether or not you compost at home!), you can purchase the completed product from a commercial composting facility. This compost is sold to landscapers, agricultural users and residents for use in their yard or garden. Head to the Recology facility in North Plains or the City-operated Sunderland Recycling Facility in North Portland for nutrient-rich compost you can add to your garden.
Thank you for your dedication to reducing food and yard waste. If you have additional questions, visit Oregon Metro’s list of composting resources and the City’s list of residential compost tips for more information about composting in the city.