How to Compost Your Halloween Pumpkins

Almost one billion pumpkins are grown annually to help us celebrate the spooky season, but most of those pumpkins are thrown in the garbage rather than being composted. As fruits and vegetables ripen and rot, they release methane gas. Methane gas, like CO2, traps heat in the atmosphere, which we want to avoid.

When organic matter is added to landfills, these gases become trapped and cannot properly break down, leading to long-term adverse environmental effects like global warming and polluted air. Contrary to popular belief, landfills simply don’t provide an atmosphere that allows organic matter to become compost. According to the Environmental Protection Agency (EPA), about 58% of methane emissions from municipal solid waste in landfills consist of compostable food waste. 

Halloween and fall decor includes lots of organic items like pumpkins, corn stalks, and mums, but luckily, we can turn them all into future soil and garden fertility. Follow these simple steps to compost your Halloween pumpkins and keep them out of landfills. 

Remove Inorganic Items Used to Decorate

If you’re really into Halloween decorations, you likely went all out and used spooky candles, wax, stickers, and paint on your pumpkins. Before composting or donating, remove anything you added to the inside or outside of the pumpkin as decoration. This could be candles, battery-powered lights, paint, or glitter that may not be safe to compost or consume. 

If you had previously gutted and cleaned the pumpkin, grab any straggling seeds left behind from the cleaning process to prevent pumpkins from sprouting in your compost pile. Or leave them for a fun experiment. The seeds may produce a funky pumpkin that you can decorate next year, closing the loop on your Halloween pumpkin supply!

If you decorated whole pumpkins, you should clean them at this point before proceeding to the next step. Cut open the top large enough to access the inside with your hand and a large spoon. Scrape along the sides to remove the pulp and stringy bits, then spoon out the innards. If the pumpkin hasn’t shown any signs of decomposition, place the “guts” into a strainer. Clean it up by removing any pulp, and save it for making a pie or pumpkin soup. If you don’t love pumpkin seeds, let them dry out and share them with birds later. 

Pro Tip: While you can simply break up a whole pumpkin and add it to a compost pile, this may attract critters or cause an odor. Consider the pile’s proximity to your home when deciding to do this. 

Bust Them Up

The smaller your pumpkin pieces are before adding them to a compost pile, the quicker and more efficiently they’ll break down. If the pumpkins are soft from age, you may step on them a few times to crush them into chunks. Otherwise, use the backside of a flat hoe or spade to break it up, using safety precautions if children or animals are around. 

Pro Tip: Invite friends and neighbors over for a pumpkin-smashing party for an added layer of fall fun. Bring your own shovel party, anyone?

Leave Some For The Birds and Critters

This step is optional, but you may leave the pumpkin pieces in your yard for a few days away from your home, allowing birds, squirrels, deer, and chipmunks to chew on the innards. This provides a sweet, nutritious meal for local wildlife that’s much appreciated, especially as they attempt to fatten up for winter. 

Precautions to take include: 

• Don’t put out seeds that have added salt or pumpkins that have been bleached during the cleaning process. 
• Place all the goodies far enough from where pets can roam to prevent quarrels. 
• Keep pumpkin seeds and bits away from high-traffic areas to prevent vehicular accidents. 
• Add pumpkins with any visible mold directly into the compost pile, as this could make animals ill. 

Add To Compost Pile

I’ll keep it simple for this article, but composting gardening debris and kitchen scraps is a wonderful way to stay environmentally focused while growing food for your family. Plus, it’s a fun thing the whole family can partake in and something cool to learn about. While composting at home can seem daunting, and getting started may be intimidating, there is lots of information on how to compost correctly, complete with ratios, tips and tricks, and guidelines to help you keep it active. You can get as advanced as you’d like by keeping track of temperatures, the amounts of materials you add, and the amount of finished product, or keep it simple by going off feels and smells. 

Generally, home gardeners should follow the recommended ratio of 2:1 to 4:1 browns to greens. Browns include carbon-rich materials like dry leaves, hay, and cardboard, whereas greens include nitrogen-rich materials like kitchen scraps, grass clippings, fresh manure, and Halloween pumpkins! A fail-safe way to measure is by the 5-gallon bucket full or tractor bucket full, depending on your scale. Mix the broken-apart pumpkins with a rake or digging fork to incorporate them and help them break down more quickly. 

Balancing Your Compost

The proper balance will provide an active pile that rapidly breaks down the added materials, doesn’t stink, and has loads of microbial activity. Pro Tip: If you notice a foul smell, sprinkle in carbon-based materials. Add more fresh garden waste if the pile seems stagnant. 

Important things to remember: 

• When starting the pile, turn it daily or every few days for several weeks until the temperature reaches 131°F (55°C) for 10 to 15 days. This temperature indicates a healthy balance of carbon and nitrogen. Turning allows oxygenation, crucial to breaking down materials and boosting the life of healthy fungi and bacteria.
• If you receive no rainfall, keep moisture levels up by spraying it with your hose daily. 
• To avoid contaminating your compost, only accept woodchips, leaves, straw, and manure from reputable sources. 
• Layer material types to keep the flow healthy. An improperly built pile has anaerobic pockets, which lack oxygen. Your pile should smell uniquely earthy and fresh. If it stinks, there are ways to fix it. 
• Once the pile is active, stop adding more materials and start a new one. 

If you’re new to composting at home and your pile doesn’t get hot enough, or you simply forget about it, don’t worry. It’s not all for nothing, and you can try it again next season. Cover the pumpkins with leaves, straw, or woodchips to protect them throughout the winter. You can also try a composting bin system or a Hungry Bin from Epic Gardening.

If you’re not squeamish, I suggest investing in a worm farm. These powerful and intriguing creatures will devour your kitchen scraps and, in return, provide you with an additive to feed your seedlings with for a boost in nutrients and microbial life. While the results of worm casting benefits vary, I think it’s a worthwhile endeavor! 

Donate Pumpkins To A Local Farm 

If you’re like me and are surrounded by farmers who keep pigs, chickens, horses, and cows, you have access to a local, hungry animal that will appreciate the boost in vitamins and fiber pumpkins provide. Many will state on their website or social media pages if, when, and where you can drop spent pumpkin decorations off for their livestock.

Dropping pumpkins off at farms is a great way to help sustain the local food system. Small-scale vegetable farmers may even accept pumpkins to add bulk to their compost pile. Just ask, and avoid dropping them without their permission. 

If you plan on sharing pumpkins with animals, organically or non-sprayed pumpkins are recommended. As mentioned, don’t share pumpkins that have bleached or visible mold, as this can be harmful to animals. 

Contact Local Municipalities 

If you live in an urban area or do not compost at home, consider contacting your county’s recycling center or a nearby composting facility. Some counties may have a pickup option available this time of year to prevent pumpkins from being tossed into garbage bins. Contact your Extension Office agent for guidance if you don’t know where to begin. 

Roast Those Seeds 

Remember those seeds you removed from the pumpkin before carving it? When thoroughly dried, you can roast them and enjoy them as a healthy, protein-packed snack!

Once cooled, store them in an airtight container, where they’ll last for a few weeks, or in the fridge for about two months. But I doubt they’ll last that long! Throw them in kids’ lunch boxes as a mid-day snack, into homemade trail mix, or atop spinach salads. 

Frequently Asked Questions