Green tomato jam is a traditional, old-fashioned preserve that turns under-ripe tomatoes into a surprisingly delicious spread. It’s a great way to use those late-season green tomatoes that never had time to ripen.
Many gardeners end up with baskets or buckets of green tomatoes when the first frosts arrive. Ripening some on the counter is an option, but green tomato jam celebrates the firm, tangy flavor of unripe tomatoes and turns them into a unique, pantry-worthy preserve.
Ingredients for Green Tomato Jam
This tried-and-true recipe produces a jam with a pleasant balance of sweet and warm spice. It’s adapted from a classic canning guide and uses the natural pectin in underripe tomatoes, along with lemon peel, to help the jam set.
For 4 pints (or 8 half-pints) you will need about 6 pounds of green tomatoes. That typically equals roughly 24 medium tomatoes, though a kitchen scale is the most reliable way to measure. This recipe works with small green cherry tomatoes or larger heirloom varieties; aim for the 6 lb total.
Note: This jam uses underripe tomatoes (the firm, green ones). If you have ripe tomatoes that are green in color, use a standard tomato jam recipe instead, because fully ripe tomatoes contain less natural pectin and require a different approach.
Full ingredient list:
- 6 lbs green tomatoes (about 8 cups chopped)
- 5 cups granulated sugar
- 1/4 teaspoon ground cinnamon (or 1 cinnamon stick)
- 1/8 teaspoon ground cloves
- 1 lemon, deseeded, thinly sliced, then quartered
Sugar helps both with sweetness and with the jam’s set. Green tomatoes are tart and not as sweet as fully ripe fruit, so this amount produces a traditional jam-like texture and flavor. If you prefer less sugar, you can reduce it to about 2 cups, but expect a lower yield and a looser, less sweet spread that will resemble a relish more than a conventional jam.
How to Make Green Tomato Jam
Begin by preparing jars and a water bath canner if you plan to preserve the jam long-term.
Core and halve the tomatoes using a sharp knife. You should end up with about 8 cups once they’re halved. Coarsely chop them by hand for a chunkier texture, or pulse in a food processor in batches—avoid puréeing if you want some texture.
Add the chopped tomatoes to a large, heavy-bottomed pot as you work. Stir in the sugar, cinnamon, cloves, and the thinly sliced, quartered lemon. The tiny pieces of lemon peel help the jam set and add subtle citrus notes. If you dislike peel, you can use only the juice, but the jam will be softer.
Bring the mixture to a rolling boil over medium-high heat and boil for 25 minutes, stirring more frequently as it thickens to prevent scorching. Reduce heat to low and simmer another 30 minutes, stirring frequently, until the jam reaches the desired consistency. If it remains watery, continue simmering until it thickens.
Remove from heat (and remove the cinnamon stick if you used one). Ladle the hot jam into sterilized, hot jars using a canning funnel, leaving 1/4-inch headspace. Remove air bubbles with a chopstick or plastic knife, wipe the jar rims clean, and apply two-piece lids fingertip tight.
You can store the jam in the refrigerator and use within two weeks, or proceed to water bath canning for long-term storage.
Canning Green Tomato Jam
Green tomatoes are fairly acidic, and this recipe includes lemon slices to ensure safe acidity for home canning. Place jars in a prepared hot water bath canner and cover with at least 1 inch of boiling water. Some cooks add 2 tablespoons of white vinegar to the canner water to help reduce mineral deposits; this is optional.
Bring the water back to a full boil and process pints or half-pints for 20 minutes. When time is up, turn off the heat and let the jars sit in the hot water for 5 minutes. Remove jars with a lifter and place them on a clean towel with at least 1 inch of space between jars. Let cool undisturbed to room temperature (about 12 hours).
Check seals and move any unsealed jars to the refrigerator. Remove the screw bands from sealed jars for storage and keep the jam in a cool, dark place. Properly canned jars maintain quality for 12–18 months. Refrigerate after opening.
Other Green Tomato Uses
If you have more green tomatoes, there are many preserving options to explore that showcase their tart, firm texture—pickles, chutneys, piccalilli, chow chow, and salsas all make excellent pantry items and pair well with meats, cheeses, and sandwiches.
Old-Fashioned Jam Recipes
If you enjoy jams made without added commercial pectin, try other fruit preserves like grape jam, blueberry jam, seedless blackberry jam, apple jam, or pear jam. These recipes rely on the natural pectin in the fruit and classic cooking techniques.
Fall Canning Recipes
Fall is a great time to preserve a variety of garden produce. Consider canning apple slices, pears, pumpkin, or beets to stock your pantry for the months ahead.
