Homemade Spiced Plum Soda: 48 Cents a Glass

Plums are the fruit I always buy too many of in the last good week, and this October was no exception. The ones left in my fridge on Sunday were too soft to slice neatly and perfect for soda. Simmered with cinnamon and a single star anise, they make a deep red syrup that tastes like the end of fall in a glass, warm spice first and tart plum underneath. It costs me about $0.48 for a 12-ounce glass at my local prices. Here is the recipe, the math, and the one spice rule that keeps it from tasting like potpourri.

The syrup: simmer the plums, respect the star anise

For one batch, about 1.25 cups of syrup, I use 1 pound of ripe plums, halved and pitted ($2.99 at my store this week), 3/4 cup of sugar ($0.27), a cinnamon stick ($0.30), one star anise pod ($0.15), a strip of orange peel ($0.09 from one $0.69 orange), and a tablespoon of lemon juice ($0.10). With a pinch of salt, the batch totals $3.90 before water and carbonation. Simmer the plums, sugar, spices, peel, and 1 cup of water for 15 minutes, mashing once the fruit collapses. Take it off the heat, rest 20 minutes, then strain and stir in the lemon. That rest matters: star anise keeps extracting after the heat stops, and one pod for this batch size is plenty. Two pods and your soda tastes like cough drops. At 2 tablespoons per glass plus about $0.09 of carbonation and ice, call it $0.39 of syrup per glass for 10 glasses, $0.48 all in, and I am rounding honestly rather than down.

The honest cost comparison

Cost per 12-ounce serving at the author's local prices, October 2026. Homemade batch $3.90 of syrup ingredients for 10 glasses, plus carbonation.

A can of store flavored sparkling water costs me about $0.75 and delivers a hint of fruit. A bottled craft soda runs $1.83, nearly four homemade glasses. The honest caveat is plum season: at $2.99 a pound in October this works beautifully. In January, when plums are imported, hard, and priced like jewelry, skip it and use frozen plums if your store carries them, or wait. This syrup also freezes well in an ice cube tray for a month, which is how I stretch one October batch into November without pretending fresh plums last that long.

Serving it cold, warm, and for a crowd

Cold is the default: 2 tablespoons of syrup over ice, topped with 10 to 12 ounces of very cold sparkling water, stirred once. The color is a clear garnet and the spice reads as warmth, not heat. Warm, it becomes something else entirely: 2 tablespoons in a mug of hot water with the cinnamon stick fished out of the strainer and reused is my evening drink this week. For a crowd, scale by three, keep the syrup and the sparkling water separate until serving, and set out orange twists if you have them. Guests who say they do not like soda usually mean they do not like sweet; this one is tart enough to change their mind, and at $0.48 a glass you can afford to let them test the theory twice.

FAQ

What does homemade spiced plum soda cost per glass? About $0.48 at my local prices: a $3.90 syrup batch pours 10 glasses at $0.39 of syrup each, plus roughly $0.09 of carbonation and ice per glass.

How much star anise should I use? One pod for a 1-pound plum batch. Star anise keeps extracting during the off-heat rest, and a second pod pushes the flavor from warm spice to medicinal.

Can I use frozen plums? Yes. Thaw them first, keep every drop of juice, and use the same proportions and simmer time. Frozen is usually the better buy outside plum season.

How long does plum syrup keep? About a week sealed in the refrigerator, or a month frozen in an ice cube tray. Thaw only what you will use in a few days.