How to Make Scented Candles in Jars

There’s something quietly magical about a candle you made yourself. You chose the jar. You picked the scent. You poured it on a Tuesday afternoon while the kettle boiled. And now it’s on your windowsill, waiting for the first match. That’s the whole reason I teach this workshop — it turns a rainy afternoon into something you can actually use.

Making scented candles in jars looks impressive but costs very little. Wax, wicks, jars, and a fragrance you love. That’s it. No special studio, no expensive equipment. If you can melt butter, you can make a candle. And once you’ve made one, you’ll never look at a sad shop-bought candle the same way again.

Materials List

• Soy wax flakes — around 500g makes two or three medium jars. Soy is forgiving, burns clean, and takes scent beautifully. Alternative: rapeseed wax or a soy-coconut blend. Avoid paraffin for your first go; it’s fussier and less forgiving.
• Cotton wicks with metal tabs — pre-tabbed wicks save you a fiddly step. Alternative: wooden wicks, which crackle nicely but need a bit more trimming.
• Heatproof jars — clean jam jars, old candle vessels, or kilner jars. Glass should be thick and free of cracks. Alternative: small ceramic pots or tin cans with the top removed and edges filed smooth.
• Fragrance oil — candle-safe, not the stuff for oil burners. Around 30–40ml for 500g of wax. Alternative: essential oils, though they fade faster and some (like citrus) are faint.
• A double boiler or a heatproof jug in a saucepan — you’re melting wax gently, not frying it.
• A thermometer — a cheap digital one is fine. This is the one tool I’d beg you not to skip.
• Wick centring tools — two chopsticks or pencils work perfectly.
• Scales — kitchen scales are fine.
• Paper towels — for the inevitable drips.

Step-by-Step

1. Weigh your wax. Fill your jar with water to the level you want the candle to reach. Pour that water into a jug, note the volume, then multiply by roughly 0.85 to get the wax weight in grams. Soy flakes are less dense than water, so a jar that holds 200ml of water needs about 170g of wax. Do this for each jar and add it all up.
2. Stick your wick down. Put a small dot of hot glue or a dab of melted wax on the metal tab and press it dead centre in the bottom of the jar. If your wick is too long, trim it so only 1–2cm sticks up above the jar rim for now. Thread the top through a chopstick or pencil laid across the jar mouth to keep it upright.
3. Melt the wax gently. Put the wax in your jug or double boiler over a pan of simmering water. Keep the heat low. Stir occasionally with a spoon you’ll dedicate to wax from now on. It takes 10–15 minutes. Don’t rush it with high heat — wax can scorch and the smell never quite goes.
4. Watch the temperature. When the wax is fully liquid, check it with your thermometer. You want to add fragrance at around 65°C. If it’s hotter, take the jug off the heat and wait. If it’s cooler, warm it briefly.
5. Add your fragrance oil. Pour it in and stir gently for a full two minutes. Not thirty seconds. Two minutes. This is where most beginners under-stir and end up with a candle that smells of nothing.
6. Pour into the jars. Let the wax cool to about 55°C first. Pour slowly and steadily, leaving 1cm of space at the top. If you see the wax pulling away from the glass as it sets, that’s normal shrinkage — just top it up with a little more melted wax once it’s fully cool.
7. Let them set undisturbed. Leave the jars somewhere level and draught-free for at least 24 hours. Resist the urge to poke them. Soy wax forms a slightly rough, creamy top — that’s exactly right.
8. Trim the wick and cure. Once set, trim the wick to about 5mm. Then — and this is the hard bit — leave the candles for 3–7 days before burning. This “curing” time lets the scent bind properly with the wax. Burn one straight away if you must, but the difference after a week is real.

Beginner Tips

Here’s the thing nobody tells you: most first candles fail for boring reasons, not mysterious ones.

• Don’t skip the thermometer. I know it feels fussy. But fragrance oil added to wax that’s too hot simply evaporates. You’ll have a lovely unscented candle and no idea why.
• Measure your fragrance properly. A common ratio is 6–10% of the wax weight. For 500g of wax, that’s 30–50g of oil. Eyeballing it gives you weak candles.
• Use the right oil. Oil burner fragrance and essential oils behave differently. Candle-specific fragrance oils are formulated to bind with wax.
• Don’t pour too hot. Pouring above 60°C can cause sinkholes, cracks, and a wick that shifts off-centre.
• Trim before every burn. A long wick makes a big flame, which tunnels the wax and can smoke. 5mm every time.
• Burn for two hours the first time. This sets the “memory” of the candle so it melts evenly to the edges.

Creative Variation

Once you’ve nailed the basic pour, try a two-tone layered candle. Make a small batch of unscented or lightly scented wax, pour it to fill a third of the jar, and let it set completely. Then make your main scented batch in a contrasting colour — a drop of candle dye goes a long way — and pour it on top. The layers stay separate as long as the first is fully cool. It looks like something from a fancy shop, and nobody needs to know it took you twenty extra minutes. You can also layer two scents: vanilla on the bottom, orange on top, so the candle changes character as it burns down.

Troubleshooting

Something went wrong? Good. That’s how you learn. Here’s what to do.

• The top has a dip or sinkhole. Totally normal with soy. Melt a little extra wax, let it cool to 55°C, and pour a thin layer over the top to level it. It’ll blend in.
• The candle smells weak. You either added oil when the wax was too hot, under-stirred, or didn’t cure it long enough. Next time, add at 65°C, stir for two minutes, and wait a week.
• The wick keeps going out. It’s probably too short or drowning in wax. Dig out a little wax around the base, let it set, and trim to 5mm.
• Wax is pulling away from the glass. Cooling too fast. Next time, pour at 55°C and let it set somewhere warm-ish, away from a cold windowsill.
• The flame is huge and smoking. Wick’s too long. Blow it out, let it cool, trim it, relight.
• There’s a crack down the side. The wax cooled unevenly. You can often save it by warming the jar gently with a hairdryer on low until the crack fuses, then letting it re-set slowly. If not, remelt the whole thing and start again — no waste.

Making candles is one of those crafts that rewards you twice: once when you pour, and again every time you light one. Start with a single jar. Keep your thermometer close. Don’t panic if the top looks a bit rustic — that’s handmade charm, not failure. And if your first batch smells faint, well, now you know exactly what to change. So what scent are you going to try first?