The size of the wick is also important: A larger wick means a larger flame, which will burn through your wax faster. (This is why it’s important to trim your wick before every use, but more on that later.) “One job of a candlemaker is to ensure that a wick is large enough to melt the full surface of the candle, but not too large that it’s drawing up more wax than necessary,” Stephen Tracy, the co-founder of Keap, explains. It’s a science, people! A candle’s burn time—usually between 40 and 60 hours—is largely determined during formulation, but there are things we end users can do to make sure it reaches its full fragrant potential. When you’re tending to your wick, be sure to also take off any curdled clumps or buildup—mushrooms, as they are called in candle land—since they, too, can cause your wax to burn too quickly. To allow your flame to melt the entire surface of the wax, you should leave it going for at least an hour—especially during those first few burns. “If you stop short, the candle will develop a memory of where the melt pool stopped previously, which can lead to tunneling,” says Stone. “Repeatedly burning a candle this way will create a smaller and smaller melt pool each time,” adds Meresz. If you do notice your candle start to tunnel, not all hope is lost! Stone says that putting a little “tinfoil tent with a silver-dollar-size open hole in the center for ventilation” on top of your candle as it burns (again, for at least an hour) can help trap heat and liquefy the entire surface again. Stand by while this is happening to make sure your tent doesn’t get knocked over. Emma received her B.A. in Environmental Science & Policy with a specialty in environmental communications from Duke University. In addition to penning over 1,000 mbg articles on topics from the water crisis in California to the rise of urban beekeeping, her work has appeared on Grist, Bloomberg News, Bustle, and Forbes. She’s spoken about the intersection of self-care and sustainability on podcasts and live events alongside environmental thought leaders like Marci Zaroff, Gay Browne, and Summer Rayne Oakes.