Rhubarb & Cinnamon Jam: Recipe, Ratios and Variations

To make rhubarb and cinnamon jam, you'll need 1 kg rhubarb stalks, 500–700 g sugar, the juice of one lemon and 1 teaspoon of ground cinnamon — simmer until soft, until a drop holds its shape on a cold plate. This quantity makes roughly three to four small jars.

One thing worth knowing upfront: rhubarb is naturally low in pectin, so without a helping hand your jam will stay runny. That's why it's worth using either jam sugar (in a 2:1 or 3:1 ratio), a dose of standard pectin, or at the very least lemon juice — it helps the set and brightens up the flavour at the same time.

• 1 kg rhubarb – stalks only, trimmed and cut into roughly 2 cm pieces

• 500–700 g sugar – granulated, or jam sugar 2:1 / 3:1 for a more reliable set

• 1 lemon – both juice and grated zest, for freshness and to help with gelling

• 1 teaspoon ground cinnamon – or 1 cinnamon stick, simmered with the mixture

• 1 teaspoon vanilla extract – optional, for a rounder flavour

1. Prepare the rhubarb. Wash the stalks, trim the ends and cut into roughly 2 cm pieces. Young spring rhubarb doesn't need peeling; with thicker, older stalks, strip off the coarser fibres.

2. Toss with sugar and leave to sit. Mix the rhubarb with the sugar and leave for at least an hour (or overnight in the fridge) to draw out the juices. This saves you both water and cooking time.

3. Simmer. Bring to the boil, then reduce the heat and let it bubble gently for 30–40 minutes. Stir occasionally and skim off any foam.

4. Test for setting.Drop a little jam onto a cold plate straight from the freezer: if it wrinkles and doesn't run when you nudge it with your finger after a few seconds, it's ready. If you have a thermometer, aim for 104–105°C.

5. Finish it off. Stir in the lemon juice, zest, cinnamon and vanilla if using, and simmer for another 5 minutes. Fish out the cinnamon stick now, if you used one.

6. Fill the jars. Ladle the hot jam into sterilised jars, filling almost to the top, seal with lids, then turn upside down for a few minutes to create a vacuum seal.

For 1 kg of rhubarb, use 1–2 teaspoons of ground cinnamon, or one cinnamon stick, which you fish out after cooking. Ground cinnamon gives a bolder, richer flavour; a stick lends a subtler, more aromatic undertone without any gritty texture. Start with less rather than more — cinnamon can easily overpower rhubarb's delicate flavour.

Cinnamon isn't the only option. Other spices work well in rhubarb jam too:

• Ginger – fresh grated or a pinch of ground; a spicy kick that plays off the tartness

• Vanilla – the seeds scraped from a single pod completely transform the flavour profile

• Cardamom – an exotic, floral note; just a few crushed pods will do

• Nutmeg – a pinch for warmth and depth

• Cloves – just 1–2, or they'll dominate everything else

Add spices towards the end of cooking so they keep their aroma.

For strawberry and rhubarb jam, a 2:1 ratio in favour of strawberries works best — that is, two parts strawberries to one part rhubarb. The sweetness of the strawberries balances rhubarb's tartness, so neither flavour overpowers the other.

Choose strawberries that are ripe but still firm; local, in-season berries with a strong aroma work best. If fresh ones aren't available, good-quality frozen strawberries do the job too — just let them drain after thawing so they don't add too much extra liquid to the jam. Strawberries also contain even less pectin than rhubarb, so lemon juice or jam sugar are doubly useful here.

Rhubarb also pairs well with other fruit. Cherries add gentle sweetness and a deep ruby colour — pit them and add roughly in a 1:1 ratio with the rhubarb. Orange brings a citrus lift; use both the juice and grated zest, replacing part of the lemon, or even part of the rhubarb, with it. Both variations can take a little less sugar, since the fruit itself brings plenty of sweetness.

You can make rhubarb jam without regular sugar, but expect two changes: you'll need to replace the missing sweetness with something else, and you'll need another way to help it set, since sugar normally helps with gelling too. Good sweetener options include honey, maple or agave syrup, and, among the calorie-free options, erythritol — according to manufacturers it doesn't ferment or raise blood sugar, but it won't help thicken the jam, so you'll need to sort out the texture separately.

Fruit with a higher natural sugar content, such as banana or pineapple, can also add natural sweetness. One thing worth noting: bromelain from pineapple, often mentioned for its digestive benefits, breaks down when cooked above roughly 70°C — so in a cooked jam it no longer plays any enzymatic role; treat it purely as a sweet ingredient.

For thickness without sugar, try:

• Pectin (ideally low-methoxyl pectin, which sets even without sugar)

• Chia seeds – a few spoonfuls stirred in near the end create a jammy, gel-like texture without any lengthy cooking

• Lemon juice – adds pectin and freshness at the same time

Mint and ginger take a classic rhubarb jam somewhere completely different. Mint adds a refreshing, summery note and softens the tartness — finely chop a few fresh leaves and stir them in right at the end of cooking, otherwise they'll turn bitter and lose their freshness. Ginger, on the other hand, adds a spicy warmth: grate fresh ginger straight into the pot, or add dried ginger with the sugar at the start.

If you're feeling adventurous, try combining mint and ginger — start with small amounts of both and adjust gradually so neither flavour overwhelms the other. If you like your preserves with a bit more heat, sweet-and-spicy chilli jams are worth trying too.

Store jam in vacuum-sealed jars somewhere cool and dark; kept this way, it'll easily last a year. Once opened, keep it in the fridge and use it up within a few weeks. Sugar-free jams or those made with chia seeds don't keep as long — treat them more like a fresh preserve to use within a few days in the fridge, or freeze in portions instead.

And what to do with it? The classics are on toast and with pancakes, but it also works brilliantly as a filling for cakes and buns, or stirred through a bowl of yoghurt.