How to Burn a Candle Properly

Wax has a memory. On the first light, the melt pool needs to reach the full diameter of the vessel, right out to the edge. If you blow the candle out before that happens, the wax will keep burning down inside that narrower ring for the rest of its life, leaving a thick unburned wall behind. That is tunnelling, and it can waste a third of what you paid for.

Allow roughly one hour per inch of vessel diameter. A standard 190g to 240g candle needs two to three hours on the first burn. A wide shallow ceramic like an Astier de Villatte needs closer to four. Do not light an expensive candle if you only have thirty minutes.

An untrimmed wick is the cause of nearly every candle problem people complain about: black smoke, soot on the glass, an oversized flame and a mushrooming carbon ball on the wick tip. Trim to about 5mm before each burn, once the wax has fully cooled.

Nail scissors work, though a wick trimmer reaches into deep vessels more easily. Remove the trimmed debris from the wax pool before lighting; leftover fragments act as secondary wicks and burn dirty.

Beyond about four hours the vessel becomes very hot, the wick starts to lean and mushroom, and the flame grows past its intended size. Extinguish, let the candle cool completely, trim the wick and relight if you want more.

This matters more with thick glass and ceramic vessels that retain heat, and it is why brands like Nest New York specifically warn that the glass runs hot on long burns.

The foil method recovers most tunnelled candles. Wrap aluminium foil around the top of the vessel, leaving a hole of two to three centimetres above the flame, then burn for two hours. The trapped heat melts the raised wax wall back down to level.

For severe tunnelling, a heat gun or hairdryer on low will melt the surface flat, though this consumes fragrance and is a last resort. Once level, restart with a proper full first burn.

Blowing a candle out sends a plume of smoke into the room and can spatter wax onto the vessel walls. A snuffer smothers the flame cleanly. A wick dipper is better still: push the wick into the melt pool then lift it upright, which extinguishes the flame with no smoke at all and pre-coats the wick for an easier next light.

Keep the lid on between burns. It protects the wax surface from dust and slows the evaporation of top notes, which is the main reason an old candle smells weaker than a new one.