- 8 cups of watermelon, black seeds removed, separated from rinds, and cut into chunks
- 1/4 cup lemon juice
- 2 boxes of No Sugar Needed Pectin (if you only add 1 box of pectin, you will end up with something akin to watermelon syrup)
- 4 cups sugar
How to make watermelon jam:
- Puree the watermelon chunks in a blender. Depending on the size of your blender, you may have to work in two batches, but the finished amount of puree should be roughly 4 cups.
- Pour the watermelon puree into a large pot. Add lemon juice.
- In a small metal bowl, whisk both boxes of pectin together with 1/2 cup of the sugar. This will prevent the pectin from clumping later on.
- Whisk the pectin/sugar mixture into the watermelon puree.
- Bring the mixture to a boil over medium-high heat. Stir almost constantly to prevent the bottom of the mixture from burning.
- You will add the rest of the sugar when the mixture is boiling so hard that you can’t stir the bubbles away. Whisk the sugar in.
- Return the mixture to a hard boil, and cook for one minute.
- After one minute, remove the jam from heat.
ou have three choices:
- Can the jam. This is my favorite option. It’s simple, as long as you have the right tools. More on that below.
- Freeze the jam up to one year. Use jars especially for keeping in the freezer, and wait to fill them until the jam mixture has cooled.
- Eat the jam. This is a good option, except that this particular recipe makes about 10 cups of jam. It will only keep a few weeks in the refrigerator, so… unless you’re going to give it all away really quickly, this isn’t a great option.
Canning Homemade Watermelon Jam
- Preheat 10 half-pint jars and 10 jar lids. We do this by running the jars through the dishwasher and boiling the lids on the stove.
- Heat a very large pot of water for canning. Preferably, this is a 20-quart or bigger pot filled about halfway with water and heated on high til the water boils.
- Get out a jar, make sure it is both clean and dry, and fill it with jam using a metal ladle and a funnel, leaving about 1/4 inch of empty space at the top.
- Wipe the top of the jar with a clean paper towel to make sure it’s clean and dry. Place a lid on top of the jar.
- Screw a lid ring on firmly.
- Repeat until all jars are full. If you have a partial jar, you should put it in the refrigerator and eat it in the next couple of weeks. Don’t can a partial jar.
- Place all of the jars into the very large pot of boiling water. Boil them for 10 minutes. (If you are above sea level, times will vary. Consult the instructions inside the box of pectin to be sure.)
- While the jars are boiling, set a dry towel on the counter (or in some other place where they can sit undisturbed for at least 24 hours). When the time is up, use tongs to remove the jars and set them in the middle of the towel. When all of the jars are out of the water bath, bring the ends of the towel up and lay it over top of the jars. This will help them to cool slowly. Honestly, I don’t know why that’s important, but my mom told me to do it.
So I do it.
- Once the jars are cooled, check to make sure they sealed. Just like the jars in the store, the lids should all be sucked down and shouldn’t give when you press on them. You’ll most likely hear this happening as the jars cool; I always listen and keep count. Because I’m a canning dork.