There's Nothing Quite Like It

Opening a jar of jam you made yourself — especially when the strawberries came from your own garden or a local farm — is one of those small pleasures that feels entirely outsized. It tastes different from shop-bought, because it is different: made slowly, with real fruit, without the preservatives and stabilisers that commercial jam tends to rely on.

The good news is that jam making is genuinely straightforward, and a strawberry jam is the ideal place to start. You don't need special equipment, and you don't need to be an experienced cook.

What You'll Need

Ingredients

  • 1 kg fresh strawberries, hulled and halved
  • 750g–1 kg white granulated sugar (see note below)
  • Juice of 1 lemon

Note on sugar: The traditional ratio is equal weights of fruit and sugar, but many people find this too sweet today. Starting at 750g gives a fruitier jam; 1kg will set more firmly and keep longer.

Equipment

  • A large, heavy-bottomed pot (preserving pan or jam pan if you have one)
  • A wooden spoon with a long handle
  • A small plate kept in the freezer for testing the set
  • Sterilised glass jars with lids
  • A ladle and a jam funnel (optional but helpful)

Sterilising Your Jars

This step matters. Unsterilised jars can lead to mould forming even in a properly made jam. It's simple:

  1. Wash jars and lids in hot, soapy water and rinse well
  2. Place on a baking tray in the oven at 120°C for 15 minutes
  3. Keep them warm until you're ready to fill them — filling cold jars with hot jam can cause cracking

Making the Jam

  1. Macerate the fruit. Place the hulled strawberries in your pot with the lemon juice and half the sugar. Stir gently and leave for at least 30 minutes (or overnight in the fridge) to draw out the juice.
  2. Dissolve the sugar. Heat the mixture on low, stirring frequently, until all the sugar has completely dissolved before bringing it to a boil. Rushing this step can cause the jam to crystallise later.
  3. Add remaining sugar and boil hard. Add the rest of the sugar, stir to dissolve, then bring to a rolling boil — one that doesn't stop bubbling when you stir it. Keep at this high heat for around 10–15 minutes.
  4. Test the set. Drop a small amount onto your cold plate. Wait 30 seconds, then push it with your finger. If it wrinkles, the jam is ready. If it runs, keep boiling and test again in a few minutes.
  5. Skim and pot. Remove from the heat. Skim any foam from the surface. Leave to cool for 5 minutes (this helps the fruit stay suspended rather than floating), then ladle into sterilised jars. Seal immediately with lids.

Setting and Storing

Leave the jars undisturbed until fully cool. As they cool, you may hear a satisfying pop — that's the lids sealing. Properly sealed jars of jam will keep in a cool, dark cupboard for up to a year. Once opened, store in the fridge and use within a few weeks.

Troubleshooting

  • Jam didn't set: Don't worry — you can tip it back into the pan, add another squeeze of lemon, and re-boil. Test the set again carefully.
  • Jam is too firm or crystallised: The sugar was probably added too quickly before dissolving. The flavour will still be good; just treat it as a thick spread.
  • Mould on top: This usually means the jars weren't sterilised thoroughly, or the jar wasn't sealed while the jam was still hot. Discard any affected jars.

Once you've made your first batch, you'll understand why so many people make jam every summer without fail. It's practical, meditative, and at the end of it, you have something genuinely beautiful to put on the shelf.