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Question: What should I do with stickers on fruits? Can I put them in a compost bin?
Answer: Stickers on fruit and veggies are made of plastic and should be removed and placed in the garbage. For more composting tips and tricks, visit our Compost Tips and Tricks page.

Question: What items are compostable? For example: milk cartons, leftover paper containers from restaurants, paper coffee cups, wax. Thank you.
Answer: Milk cartons should go into your recycling cart, as they have valuable paper that can still be recycled. Paper containers from restaurants and paper coffee cups can be composted, so long as they are made completely out of paper or lined with wax. Wax paper like the paper that usually wraps sandwiches also goes into the compost cart. Learn composting tips and tricks here. A list of accepted and unaccepted items can be found here.

Question: Should I use the food disposal in my sink? Is it better to compost? What happens to the food at the end of the process.
Answer: Food that you send down your disposal ends up going to a wastewater treatment plant, where it gets processed, but there’s no guarantee that it will be used beneficially. It is better to compost your food because it will get processed and turned into finished compost, where it has the chance to be used in versatile ways. For example, finished compost gets sold to farmers, vineyards, and even a portion of it gets sent back to our community, where residents can get it for free to use in their gardens or house plants.

Question: Are biodegradable compostable plastic bags accepted in Redwood City’s industrial composting process?
Answer: Yes, compostable bags are accepted. The bags must be say “Certified Compostable,” and they are usually a light green color.

Question: [Is] there any compost bag available in the market that I can use for holding compost trash so that they won’t stink up the compost bin and attract bugs / animals? Please advise. Thank you!
Answer: You can use BPI certified compostable bags to hold your organic waste. You are welcome to use a plastic bag as well, we just recommend that when you empty the contents into your compost cart, you throw the plastic bag into the garbage cart as plastic does not belong in the compost cart.

Question: Are Chinese take-out boxes compostable? (the ones that has waxy coating, without a metal handle)
Answer: Paper-based take-out boxes with wax only lining, such as those found from Chinese restaurants can go into your green compost cart. Some may be lined with plastic and those cannot go into your compost cart. For more composting tips and tricks, visit our Compost Tips and Tricks page.

Question: I live in an apartment complex and there isn’t a compostable bin to dispose organic waste. I used the sink disposal but they get blocked frequently. I feel guilty disposing compost-able waste in trash. What are my options. Please advice.
Answer: 1) Consider starting a worm composting bin where you put your organic waste in; worms eat it and it becomes rich compost. For more information, the County of San Mateo has a page dedicated on how to get started, and they offer rebates if you buy a worm bin through them. 2) Reach out to your property manager to inquire about getting compost service at your apartment complex. Most likely there are other residents that inquire, so finding support will only better your chances! 3) Community gardens likely have their own composting system that may allow residents to drop off their organic waste in, similar to this program Collective Roots in East Palo Alto has. Check to see if there is a local community garden near you that may have a similar offer.

Question: Are leaves ok for compost pail?
Answer: Leaves can be placed in your kitchen compost pail. Anything that is accepted in your green compost cart can go into the kitchen pail as you will place it in your compost cart (it’s really about what will fit in the pail vs what will not). If you have more questions about what is and what isn’t accepted in your compost cart, please visit

Question: More detailed list of what can go into the compost bin. I know there’s the video but the video said to avoid animal things and on the actual bin there are pictures that says animal bones are ok.
Answer: You can find a complete list of what can go into your green compost cart here. While meat and bones are accepted in the compost cart, animal or human waste is not as they can contain bacteria and pathogens not accepted through out commercial composting facilities.

Question: How come food does not compost in the garbage?   Are toothpicks ok to compost?   Is regular carton ok to compost or just food stain paper products? Christmas just passed and my neighbor,  whom I shared bins with, placed cardboard boxes from the Christmas presents into the compost bin [because] the recycle bin was full.
Answer: Food scraps in the garbage go to the landfill and while the food will break down in a landfill, the material that breaks down becomes a powerful contributor to greenhouse gas emissions. Compostable materials, such as food waste and paper, decompose anaerobically (without oxygen) in a landfill, producing methane (CH4). Toothpicks are accepted in the green compost cart. Milk or juice cartons from the refrigerated section of the grocery are accepted in the blue recycling cart, while shelf stable cartons (think soy or non-dairy milks) go into the garbage. These cartons are aseptic containers (also known as Tetra Paks) and are made out of plastic, paper, and aluminum, making it difficult to separate the materials individually to recycle. Clean cardboard boxes should be placed in the blue recycling cart. If your recycling cart is full, you can bundle up flattened cardboard boxes and place them next to your recycling cart – just make sure it is not raining on your collection day. If cardboard boxes become wet, they can then go into your compost cart.

Question: I am still not clear on wax paper, paper towels – blue or green bin? Is it Ok to put food waste in plastic bags – I dislike getting my bin fouled up with spoiled food.
Answer: Wax paper and paper towels can be placed into your green compost cart. Food scraps cannot be placed into plastic bags. You may use BPI (Biodegradable Products Institute) certified bags to collect your compostable materials in. Other ideas to help keep your cart cleaner:

  • Collect your compostable materials in newspaper/junk mail/ads, a paper bag, or soiled cardboard.
  • Layer your compost cart with leaves/grass clippings/other landscape materials or soiled cardboard

Question: Can bioplastics be composted?
Answer: Only materials that are BPI (Biodegradable Products Institute) certified can be placed in your compost cart.

Question: Can you help explain the industrial composting vs home composting better?
Answer: Industrial compost is a large-scale composting mechanism that is designed to handle a large volume of organic waste that can heat the materials to a high enough temperature to break down everything that is collected from composting programs. This differs from home composting (backyard or worm composting) where conditions only allow for certain materials to be composting (i.e. the temperature does not get that hot enough to break down certain materials). You can find more information about home composting at San Mateo County’s Office of Sustainability website.

Question: Not sure if I missed it, but information regarding types of backyard composting residents could do (collect autumn leaves and build their own compost pile), compost bins for purchase or rebate through San Mateo county program, worm composting info…
Answer: The goal of our Rethink Compost campaign was to focus on using the green compost cart at home. Information about home composting methods can be found at San Mateo County’s Office of Sustainability website.

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