To make a candle last, let the first burn run until the melted wax reaches the edge of the candle, trim the wick to about 5 mm before every burn, and never burn it for more than about four hours at a time. These three habits stop tunnelling, smoke and black marks, and they make the candle burn evenly to the end.
Why does the first burn matter? Wax has a memory. If you blow a candle out before the melted pool reaches the edge, it will melt to the same line every time after, and dig a tunnel down the middle. As a guide, allow about one hour of burning for every 2.5 cm of the candle’s width. A candle 7.5 cm wide needs about three hours the first time.
Why trim the wick? A long wick makes a tall, flickering flame that smokes and leaves soot on the glass or the wall. Before you light the candle, trim the wick to about 5 mm. Use scissors or a wick trimmer, and do it when the wax is cool.
How long can a candle burn? Up to about four hours at a time. After that the wick grows long, the flame grows tall, and the candle can overheat. Let it cool for a couple of hours before you light it again.
Where should a candle stand? On a heat-safe holder or plate, away from fans, open windows and air conditioning vents. Moving air makes the flame lean, and the candle burns unevenly and drips. Keep it away from curtains, shelves above, children and pets.
How do you put out a candle? Use a snuffer, or dip the wick into the melted wax with a tool and straighten it again. Blowing scatters hot wax and makes smoke. Stop burning a candle when about 1 cm of wax is left at the bottom.
Three quick answers
How long should the first burn be? About one hour for every 2.5 cm of the candle’s width, until the wax melts to the edge.
How short should a wick be? About 5 mm, trimmed before every burn.
Why is my candle tunnelling? The first burn was too short. Let it burn longer next time so the pool reaches the edge.
