Many people are surprised to learn that potato skins (aka peels) are packed with vitamins and nutrients and can also be a good source of fiber. Many regularly cook young, new potatoes peel-and-all and enjoy the health benefits the peel brings. Mature potatoes develop a tough skin that is typically removed before cooking — with the exception of baked potatoes, of course. But you don’t need to throw them away. Potato peels can be composted in your compost bin to return the nutrients to the soil.
Do potato peels add nutrients to compost?
Potato peels contain nitrogen, phosphorus, potassium, and magnesium and release these vital nutrients to the soil when they are composted. Nitrogen, phosphorus, and potassium are essential macronutrients needed for all plant growth, while magnesium helps to build healthy cell walls and speeds germination.
- Nitrogen: Nitrogen is part of the chlorophyll molecule and gives plant leaves their green color. Nitrogen is necessary for your plants to perform photosynthesis and plays a major significance in shoot growth and fruit quality.
- Phosphorus: Phosphorus also plays an essential role in photosynthesis as it helps build nucleic acid, proteins, and enzymes necessary for healthy roots, stems, and stalks. It also helps plants mature properly.
- Potassium: Potassium helps plants with the movement of water and nutrients. It also helps the plant regulate the opening and closing of stomata, the ‘breathing’ pores found on the undersides of leaves. This helps the plant exchange oxygen and carbon dioxide and to release moisture as needed, explains the University of Minnesota Extension.
- Magnesium: Magnesium is essential for building strong cell walls and assisting in good germination.
Can you compost potato peels?
Nearly all organic kitchen waste can be composted successfully in the compost bin, and potato peels are no exception. Like other vegetable scraps, potato peels are an excellent source of green (or nitrogen) material for your compost bin.
Can you compost peelings from green or sunburned potatoes?
Sometimes the outer skin of potatoes turns green when exposed to the sun (or artificial light). When this happens, there is a build-up of solanine in the skin, giving it a bitter taste and posing a risk of solanine toxicity if ingested. The solution, of course, is to remove the green skins and any underlying green flesh before cooking the potatoes.
But don’t worry. Those green potato peels can be composted safely in your compost bin as the solanine will break down when it composts.
Important Points About Composting Potato Skins
Potato skins are composted the same way other vegetable scraps are composted, but there are a few things to keep in mind.
- Treat potato skins as green material.
- Bury the skins in the middle of the pile.
- Do not compost potato peels (or foliage) from potatoes infected with blight. Pathogens may survive composting and infect new plants the following year.
- Shred the peels for faster composting.
How do you compost potato peels?
Potato peels can be added to the compost bin regularly and worked into the existing pile. However, shredding or chopping them into small pieces will help speed up the decomposition of the potato peels.
How long does it take for potato peels to turn into compost?
The decomposition rate varies depending on your compost bin’s temperature, moisture level, and health. As a rule, it takes 3 to 6 months for potato peels to compost, but it may take longer. According to the Connecticut Dept of Energy and Environmental Protection, composting in a compost bin or compost pile can take anywhere from two weeks to two years.
But there are ways to speed up the decomposition process in your compost bin.
- Keep the compost moist. If you do not receive adequate rain, spray down your compost pile with the sprayer attachment on your hose. The compost should feel like a damp sponge.
- Turn the compost once a week to allow air into the pile. Oxygen is vital to decomposition and prevents organic matter from becoming slimy and stinky as it decomposes. Turning the pile ensures that oxygen reaches the center of the pile and that it can decompose properly.
- Shred your potato peels (and other kitchen scraps) before composting them. Although it isn’t necessary to shred or chop your potato peels, smaller pieces of organic matter break down faster than larger pieces, which will help speed up the process.
- Keep a proper ratio of brown (carbon) and green (nitrogen) materials. While most experts recommend a ratio of 30 to 1 of brown (carbon) to green (nitrogen) by weight, the University of Illinois Extension recommends a simpler method of adding equal parts of brown and green material by volume (instead of by weight) and adjusting as necessary.
- Use a composting barrel that can be turned easily. A commercial composter is designed to speed the composting process when used following the manufacturer’s instructions.
Can I eat the food grown with compost made with potato peels?
Finished compost from potato peels and other kitchen and yard wastes can be used successfully to amend your garden soil. Compost does more than add nutrients to the soil. It improves the soil texture, promotes good drainage, and increases aeration.
Because the organic matter has decomposed, it becomes part of the soil. Finished compost should be dark and crumbly and smell like fresh earth. If your compost still has visible pieces of food or other material or smells bad, it is not ready to be used in the garden.
While you could grow vegetables in compost, it is generally recommended that you use your compost to amend the existing soil in the garden. During the growing season, you can add compost as a side dressing and mix it into the soil with garden tools or as a mulch around the base of your vegetables.
Composting your potato peels is a great way to reduce waste while returning nutrients to the soil. Compost makes an excellent soil amendment and provides a good source of slow-release nutrients to the soil. It also improves soil texture, promoting good drainage and increasing its water-holding capacity. The organic matter in compost also increases the aeration of the roots of your plants.