Wax has a memory. The first time you light a candle, the flame melts a pool outward from the wick, and wherever that pool stops, it tends to stop every time after. Put it out after half an hour and you get a narrow well down the middle with a wall of unburnt wax around it. That’s tunnelling, and it wastes a good part of the candle.
So the first burn is the long one. Light Low Light when you have an evening ahead of you, and let it go until the melted wax reaches the edge of the jar. For a candle this size that usually takes two to three hours. After that, shorter burns are fine, because the candle will melt back to the same edge.
Two more habits
Trim the wick to 5 mm before every lighting. A long wick makes a tall, restless flame and leaves soot on the glass. And don’t burn for more than four hours at a stretch. Let the wax cool and set, then start again.
If it has already tunnelled
It can usually be rescued. Wrap a loose collar of foil around the rim, leaving the centre open, and let it burn for a long session. The foil reflects heat back onto the wall of wax until the surface levels out.

















