Introduction: Penny Pincher's Pumpkin

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Penny Pincher's Pumpkin, Or: Getting the Most Out of Your Pumpkin

Want to get the most out of your pumpkin? When carving a pumpkin, a lot of people save its seeds and roast them, and people also save other parts of the pumpkin and turn them into pumpkin pie. But there’s actually a lot more that can be done with a single pumpkin, including making a festive serving platter (or serving bowl) for a holiday party, saving seeds to grow pumpkin plants next year (and many years to come!), and turning the used jack-o-lantern into a composter!  In fact, there’s so much you can do with a pumpkin that you should not need to ever throw any of it in the trash.

Here’s what will be explored in the Penny Pincher’s Pumpkin:
  • Making a festive serving platter (steps 2 to 5)
  • Roasting seeds (step 6)
  • Saving seeds to grow pumpkin plants (step 7)
  • Making pumpkin puree for pies and more (step 8)
  • Turning the festive serving platter into a unique jack-o-lantern (step 9)
  • Making a compost-o-lantern (steps 10 to 11)

Step 1: Materials You'll Need

For every part of this project you’ll need a large pumpkin.  Depending on what else you want to do with the pumpkin, you’ll need some other materials and tools, but they’re all inexpensive, and/or common household items. Here’s what else you’ll need to gather for each part of this project:

Making a festive serving platter (step 2 to 5):
  • Pumpkin carving knife
  • Ruler or tape measurer
  • Toothpick
  • Permanent marker
  • Pumpkin scraper or spoon
  • Food to put on your platter! Gelatinous dishes, like cranberry sauce, work well. It’s also great for serving chips and dip. 
Roasting seeds (step 6):
  • Strainer
  • Oven
  • Bowl
  • Olive oil
  • Baking sheet
  • Parchment paper
  • Salt, lemon pepper, and/or other seasoning, as desired. 
Saving seeds to grow pumpkin plants (step 7):
  • Strainer
  • Paper towels
  • Envelope 
Making pumpkin puree for pies and more (step 8)
  • Pumpkin scraper or spoon
  • Oven
  • Oven-safe baking dish, e.g. Pyrex
  • Food processor or blender 
Turning the festive serving platter into a unique jack-o-lantern (step 9):
  • Pumpkin carving knife
  • Optional: Miniature pumpkin
  • Candle
  • Matches or lighter 
Making a compost-o-lantern (steps 10 to 11):
  • Three buckets
  • “Brown scraps,” e.g., dry leaves, dry yard clippings, untreated cardboard, egg shells, etc.
  • “Green scraps,” e.g., grass clippings, old fruits, old vegetables, recently dead plants, etc.
  • Soil
  • A place outside to let the compost-o-lantern make some compost for a few weeks to months 

Step 2: Making a Festive Serving Platter, Part 1

First cut a small opening at the top of the pumpkin. You don’t want the hole to be too big because it’ll give you less room for your serving platter. 

Clean out the inside of the pumpkin like you’d normally do when making a jack-o-lantern. Scoop out the seeds set them aside in a bowl for now – they’ll be important in steps 6 and 7.  Try to keep as little slimy gunk on the seeds as possible.  Instead, separately save the slimy, stringy gunk – it can be used in the compost-o-lantern later, in step 10.  Lastly, if you scrape any harder pumpkin material out, set it aside too – it’ll be important for making pumpkin puree, in step 8.

Step 3: Making a Festive Serving Platter, Part 2

With the pumpkin cleaned out, make a long, horizontal cut near the bottom of the pumpkin. Try to find a flatter part on the pumpkin to do this. I made my cut about 12.5 centimeters (cm) long, and this worked well. (I found that if you make it much longer than this, the curvature of the pumpkin makes the serving tray not fit in place well.)

Next you’ll want to figure out how thick your pumpkin is. (This is so you can make the base of your serving tray just thick enough to slide into slits you’ll make – if you look at the pictures below, this will make sense.) To figure out your pumpkin’s thickness, push a toothpick in the cut you just made so that you can see the toothpick poking out on the inside of the pumpkin. Mark both exposed ends of the toothpick using a permanent marker. Then pull out the toothpick and measure the distance of the marks. 

Step 4: Making a Festive Serving Platter, Part 3

At one end of the horizontal cut you made, make a perpendicular cut, going towards the top of the pumpkin. Make the length of this cut equal to the thickness of your pumpkin (which you figured out in step 3). For example, my pumpkin was 4.2 cm thick, so I made the cut 4.2 cm tall.

Then make another cut that is horizontal again, going above the first cut you made. This cut should be about 3 cm long. This will be the base of your serving tray, and will slide into place in the pumpkin.

Repeat this on the other end of the original horizontal cut you made.

Then, make a large, rounded cut, going towards the top of the pumpkin, that connects the two ends. This will be your serving platter. See the pictures for an idea of what this should look like.

Carefully remove the serving platter that you cut out. Try to wedge the base of the platter back into the pumpkin, as shown in the pictures above. If the platter does not fit well, don’t worry – use the pumpkin carving knife to cut away some small pieces of the pumpkin that look like they’re getting in the way of a snug fit. Tip: Don’t cut away much along the squared, cut-out ends of the pumpkin or the serving platter won’t fit snugly anymore.  You want a tight fit.

Once you're happy with the fit of your serving platter, go on to the next step.

Step 5: Making a Festive Serving Platter, Part 4

Now scrape out the serving platter (using a pumpkin scraper or spoon) to make a depression in it, like a small bowl.

When it’s ready, put some food in the serving tray! Gelatinous dishes, like cranberry sauce (shown in the pictures), work well. It’s also great for serving chips and dip (also shown in the pictures).

Tip: If you’re making this for a party, I’d recommend carving the pumpkin and making this serving platter on the same day as the party so that the serving platter doesn’t get too old to use! If you can’t do this, then try lining the platter with plastic wrap and place the food on top of the wrap.

Step 6: Roasting Seeds

Important note: If you want to save some seeds to grow pumpkin plants, do not use all of your seeds in this step – set aside about 30 to 50 seeds to use in step 7. 

Preheat the oven to 400 degrees Fahrenheit. Take the seeds that you want to roast and rinse them in a strainer until they look really clean, without any orange pumpkin gunk on them. Transfer the clean seeds into a bowl and mix in about a tablespoon of olive oil, depending on how many seeds you have.

Spread the oiled seeds onto a sheet of parchment paper on top of a baking sheet. Arrange the seeds in a single layer. Season the seeds with salt, lemon pepper, and/or other seasoning, as desired, sprinkling a little bit all over the seeds – season to taste. Cook the seeds until they’re brown. (This may take about 30 to 40 minutes.)

Eat the seeds fresh and warm, and/or save some for later!

Here are some other Instructables on making roasted pumpkin seeds, if you want more details:

Step 7: Saving Seeds to Grow Pumpkin Plants

Take about 20 to 50 good-looking pumpkin seeds (ones that are large, plump, and don’t look damaged) and rinse them in a strainer until they look really clean, without any orange pumpkin gunk on them. Let them drain in the strainer for an hour or so.

Put the seeds on a folded paper towel (or multiple paper towels, if you’re saving a lot of seeds). Spread them out into a single layer, and don’t let them touch each other. (If they touch each other, they could get stuck to each other.) Place them in a cool, dry location for about a week, but don’t forget about them – after they’ve been there a day or two, move the seeds around a little so that they won’t get stuck to the paper towel.

After they’ve been sitting out for about a week, transfer the seeds to an envelope. Store the envelope of seeds in a refrigerator until you want to sprout some pumpkin plants in the spring!

I’ve used this method for several years now and it works great. I get at least 90 percent germination rate.  I like to save a lot of seeds so I can grow extra plants (I usually give them away to friends/neighbors) and use the same seeds for many years. I’ve had a great germination rate using the same seeds 2 or 3 years later.

Tip: When you want to grow some pumpkin plants in the spring, I recommend sprouting them between the layers of a folder, damp paper towel in a sealed plastic bag. Check on them every day to see if they’ve sprouted. I like this approach better than just sticking them in the ground because you don’t know what’s happening down there in the soil. As soon as they sprout (the root tip will come out first), carefully plant them! Make sure not to break the root tip!

Step 8: Making Pumpkin Puree for Pies and More

You can make delicious pumpkin puree (like the canned pumpkin you get in the grocery store) using the more solid parts of the pumpkin. If you don’t want to use a whole pumpkin to do this, but just the bits and pieces from a carved jack-o-lantern, then use a pumpkin scraper or spoon to scrape out the harder parts inside of the pumpkin. (Don’t use the stringy gunk.) You can also cut the solid parts off of any pieces you carve out of the pumpkin, as shown in the picture above.

Preheat an oven to 400 degrees Fahrenheit. Place all of the more solid pumpkin bits into an oven-safe baking dish, like a Pyrex tray. (If there isn’t much liquid, add a little bit of water to the tray.) Bake the pumpkin for 30 minutes.  Then process the baked pumpkin in a food processor or a blender to create pumpkin puree.  You can use the pumpkin puree immediately or store it for later.

You can use the pumpkin puree in many dishes, including pumpkin pie, pumpkin soup, pumpkin bread, and pumpkin cookies.  Personally I like to use pumpkin puree in my oatmeal to make “pumpkin pie” oatmeal, and here’s how I do it:
  • Mix ¾ cup old fashioned oatmeal with water (or milk)
  • Add a pinch of nutmeg, ginger, and allspice
  • Microwave
  • Mix in 1/2 tablespoon butter, 1/3 cup pumpkin puree, and 1 teaspoon maple syrup
  • Eat and enjoy! 
Here are some pumpkin puree recipes from other Instructables:

Step 9: Turning the Festive Serving Platter Into a Unique Jack-o-Lantern

If you have a pre-Halloween party that you use the pumpkin serving platter at, you can still re-use it as a jack-o-lantern for Halloween.  You’ll just need to be creative.

I ended up turning the cut-out part into a giant mouth, and using the platter as the tongue. I carved sharp teeth around the “mouth” and added two small eyes above, and to the sides of, the mouth. I also had a small pumpkin I carved to make it look like the large pumpkin was eating it. When you’re happy with your jack-o-lantern, put a candle inside of it and light it up!

Step 10: Making a Compost-o-Lantern, Part 1

So Halloween’s over and the jack-o-lantern is looked a little worn out. But don’t throw it in the trash!  If you don’t have a composter to toss it into, you can make a composter out of the jack-o-lantern itself! 

To make your compost-o-lantern, you’ll first need to collect some supplies. You’ll need enough compost “scraps” to at least fill up the inside of the pumpkin. You’ll want about half “brown” scraps (which are nitrogen-rich) and half “green” scraps (which are carbon-rich).  Brown scraps can be dry leaves, dry yard clippings, untreated cardboard, egg shells, or other items (see the link to Science Buddies below for details). Green scraps can be moist grass clippings, old fruits, old vegetables, recently dead plants (still green), and more. You’ll also need a small amount (about one cup) of soil.  Don’t use any scraps/soil that have been treated with chemicals.

For my scraps, I gathered a bucket of dead leaves (brown scraps), a bucket of grass clippings and cut-up spoiled vegetables (green scraps), and a bucket with some soil.  For best results, cut the scraps up so that none are longer than 5 cm.

To find out more about what scraps you can use, see Table 1 here:

Step 11: Making a Compost-o-Lantern, Part 2

Seal up the jack-o-lantern as best you can, using its cut-out pieces if possible. After removing the candle, fill the bottom of the jack-o-lantern with a layer of about 7 to 8 cm of brown scraps. Then add a layer of about 7 to 8 cm (or less) of green scraps. Then, if there’s still room, add a layer of brown scraps while mixing in some handfuls of soil as you add the scraps. This layer can be up to 10 cm thick. At this point, I reached the top of my jack-o-lantern, but if you’re using a larger one, keep filling it with layers (alternating brown, green, brown with soil, green, etc.) until you reach the top. When you’re done, replace the lid.

Take the compost-o-lantern to a place outside where it can compost for a few weeks. I half-buried mine in a garden. I’d recommend at least partially burying it so it does not fall apart too easily. If you have problems with squirrels or other animals getting to it, you can completely bury it. 

If you want to help it compost faster, use a compost aerator or gloved hands to mix the pumpkin’s contents once a week. You can also continue to add scraps as the level of the pumpkin’s contents decreases (as the scraps decompose). After several weeks, it should start to look dark and crumbly, like compost! When it’s ready (which could be several weeks to a few months, depending on the exact conditions), the nutrient-rich compost can be used in gardens and on trees!

This idea is based on a science project idea by Science Buddies – you can read more about making a composter there:

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