As a candle maker, I get asked questions about burning candles all the the time, so I thought I'd do a quick post with some frequently asked questions.
Which candles last the longest?
The larger your candle, the more likely it is to burn for a long time. That said, the size of the candle isn't the only measure of how long it will last. The burn time of a candle has to do with the combination of the wax, wick size, jar, and the room that it's burned in.
Generally speaking, a 400g scented candle made with soy wax should have a burn time of around 55-60 hours, but you can sometimes see them listed with an 80 hour burn time. If that's the case, it means that the candle maker has used a smaller wick. Although you won't get a full melt pool (when the wax burns all the way to the edges after about 3 hours) on the first burn, it should burn for a longer time.
My scented candles are 400g and have a burn time of 60 hours. They've been designed and tested that way, because it ensures you get a full melt pool on the first burn after 3-4 hours. A full melt pool means the scent will fill the room from the beginning, allowing you to enjoy your candle for the optimum amount of time.
You'll also find that a small candle in a large room won't fully scent the room - so that's something to note as well.
Pictured: The Miles: Australian Wildflowers candle
Should candles have lids?
My large candles always have lids, and the primary reason is that it keeps the dust out! A clean candle with no dust in it, looks better and burns more cleanly. When your candle isn't lit, always ensure the lid is on but never extinguish your candle by putting a lid over a burning flame.
Should candles flicker?
The size of the flame matters because a candle with a huge flame that flickers a lot, probably hasn't been made/tested correctly or the wick hasn't been trimmed. For this reason, make sure you buy your candles from someone who has done extensive testing (hi there!) and has the burn time clearly listed in the product description.
The flame should flicker slightly when it's lit, but if the flame is huge and dancing around, try to trim it - or purchase a different candle.
Pictured: The Banjo: Lemon Squash candle
Can candles explode?
Oh my goodness - absolutely! In my candle groups I see photos of exploded or broken candle jars all the time.
The main reason for an exploding candle is if you haven't read the candle care directions properly and have burnt the candle all the way down to the metal tab. If the jar gets too hot, it may crack which can cause it to explode and glass to shatter. Good candle makers like myself have insurance for these incidents but to prevent your candle from exploding, and ensure you burn it cleanly and correctly, always read the directions and burn it as instructed.