Frosting is the term used when your candle develops a white crystalized effect. Frosting is a natural occurrence where by the wax tries to return to its natural state. All soy waxes do frost and it is a sign that you are using 100% soy wax.
Some people see frosting as a defect, mostly because they feel it reduces the visual appeal of the candle. However, It does not effect the performance of a candle. Your candle my also develop frosting after burning as the candle rehardens and may also frost over time.
How can I stop frosting from occurring?
Frosting only occurs when an all-natural plant wax is used. If you use additives or blend your soy wax with a non vegetable wax, the molecular structure of the wax is changed and the wax will not frost. If you do not like frosting and don't mind using a soy blend was there are a number of alternatives you can use such as a soy-paraffin blend that will stop your candle from frosting.
Some candle makers also choose not to add colour to their candles as this increases the likelihood of frosting and makes it much more noticeable.
Soy wax is very sensitive to temperature fluctuations. Try and keep your room temperature as consistent as possible, particularly in the first 24 hours of pouring your candle.
Heating your candle jar prior to pouring can also help to reduce frosting. If they candle cools to quickly this can increase frosting. By heating your jars first this helps to slow the cooling time and helps the candle to cool more evenly. Adding tin foil around the jar can also be helpful. You can heat your jars by either using a heat gun (your best friend when it comes to candle making!) or you can place them in a pre warmed oven set to no more than 100 degrees Celsius for 1 to 2 minutes.
Try pouring at a lower temperature. It is always good to start with the wax manufactures recommendations for pour temperature. However, as noted above, soy wax hates temperature fluctuations. Particularly during winter months it can be difficult to keep the environment a consistent temperature. My candle studio is set up in the garage so controlling the temperature is almost impossible. I have found pouring at much lower temperatures of 45-50 degrees Celsius reduces frosting significantly and leaves smooth tops. It will take some trial and error to discover what works best for your environment. Some information I have read says to pour higher but I found this increases frosting in my candles rather than reducing it. But test out different pour temps + or - 5 degrees at a time to see what works best for you.
Switching to solid jars that are not see through is also a common way to disguise frosting and wet spots.
Adding Coconut blending wax or Coconut Oil can also help.
Soya wax continues to hardens throughout its life however, the first two weeks after pouring is the most critical time in which most of the hardening occurs. You can temporarily fix frosting by using a heat gun. Hold the heat gun on top of the candle until the surface is melted again. This will help to give a smoother finish to the candle wax. Slowly heat the areas of the candle with frosting. Try to ensure a consistent heat across the candles as you want to promote an even cooling of the candle.
Frosting candles can be the most frustrating and tricky part of creating soy wax candles. As frosting is a natural effect of soya wax it can be difficult to prevent altogether but there are some ways we can try to reduce it.