Why Is My Soy Wax Not Hardening?

Soy wax is a non-petroleum-based wax, it’s a hydrogenated soybean oil extruded when you freeze soybeans at -30oF.  Unlike paraffin wax which uses additives like stearic acid to enhance its quality, Soy wax is naturally of high quality. Soy wax is made from a biodegradable and renewable source that poses no threat to the environment. It can be used to produce a lot of things in addition to candles.

Some Soy wax candle and wax melt producers usually experience the challenge of non-hardening amidst others during the production process. This owes to the fact that Soy wax is generally soft and has a low melting point. Hence, to ensure their durability and strength, soy wax candles usually come in glass, metal, or ceramic containers. Aside from its natural composition, other reasons can make your soy wax not harden. Either on its own or while using it to make candles.

a photo of a soy wax candle that has not harden
Ok this picture is a little extreme but if you do not get it correct your soy wax may not harden.

The quick answer

First off before I start the problem solving guide I want to quickly answer the main question.

So why does soy wax not harden sometimes? There are a number of reasons why Soy wax does not harden sometimes. The biggest causes of this are usually an excess amount of fragrance oil in the wax, moisture getting into the wax during the melting process and also poor quality or expired Soy wax being used in the products.

What Causes Soy Wax Candles To Not Harden? 

Every production process has procedures, rules, and laid down processes which when not followed properly may lead to an undesired result.  Here are the things that could cause soy wax candles to not harden.

• Excess Moisture

If the soy wax for your candle contacted moisture heating it may not be enough to make the moisture evaporate. It’s always good to check your soy wax supply for dampness. Also, try heating up to a temperature around 185oF a bit longer than necessary. This will at least make some of the excess moisture evaporate.

• Excess Fragrance oil

 Adding excessive fragrance oil to your soy wax candle will make it look wet with ‘gooey’ spots. It will never harden because Soy wax can become semi-solid at room temperature while fragrance oil never does.  The maximum fragrance oil load for soy wax candles is 10%. This implies that for a pound of soy wax, you are to use 1.6oz of raw fragrance oil. 

• Expired wax

It takes time before the soy wax candle expires but when it does, it smells so bad.  The wax becomes softer even at room temperature and looks limpid. Candles made from this type of soy wax may not harden.

• Higher Temperature

 If the temperature of your working room is too high, your soy wax candle will not harden. It’s always advisable to work in a fully ventilated room with AC if possible.

• Poor Fragrance Oil Mixture

 Your soy wax candle may not harden if you didn’t mix the Soy wax and the fragrance oil properly. The fragrance oil will be in excess in some parts of the mix and will affect the hardening process. Ensure you stir the mixture gently and continuously until there’s a perfect mix. By doing this,  you will also prevent air from being trapped in the mixture.

• Wax not Heated well

 Heat the Soy wax for your candle to a minimum temperature of 185oF. This is to ensure a perfect blend with the dye and fragrance oil. The properly heated soy wax encases the fragrance oil which is liquid on solidifying. Failure to heat it well, the soy wax will solidify leaving the fragrance oil behind as the mixture won’t be homogenous.

• Fragrance Type

 Using a fragrance oil that is not compatible with soy wax will make the mixture heterogeneous. The Fragrance oil will always isolate itself leaving little oil droplets in the candle wax that looks like beads. 

What Causes Soy Wax Melts To Not Harden?

Soy wax melts are scented, wickless lumps of soy wax molded into cubes or other shapes. They release their scents as they melt when placed in a wax warmer (Learn more about wax melts in this guide).  If your soy wax melt is not hardening then check the following reasons below;

  • Did you add other ingredients to the soy wax at an early stage? You should allow the soy wax to heat up to a temperature between 180-185oF. At this stage, you can then remove it from the heat source and add up your fragrance oil, color, etc.
  •  Are you using the wrong fragrance oil? you may end up not having a perfect mix and this can affect the hardening process. Some raw fragrance oils will blend easily with your soy wax and give them an amazing look. Always ensure you use them in the right proportion.
  • • Do you pour out the soy way melt when it’s still too hot? It will make it not to harden. Allow the mixture to cool down to a temperature between 135-140oF before pouring into your mold. 

How To Make Sure Your Soy Wax Hardens

Hard soy wax is usually more durable. They are strong and don’t burn off quickly. Let’s look at ways to ensure your soy wax hardens.

  1. While melting your soy wax, use a double boiler at medium temperature. Avoid contaminating the wax or wick with water, it creates pockets in the wax which can cause crackle during burning.
  2. Add additive ingredients in the rightful proportion into the wax. For instance, you can use 10% of stearin and a tablespoon of clear crystals for a pound of soy wax.
  3. Carefully pour the wax into the desired container, position the wick and then allow it to cool and set. Make sure you place the wick at the centre. This will make the candle burn evenly and also help to retain its life span.
  4. Trim the wick up to a quarter-inch section ensuring that it’s centred standing up straight. 
  5. Remember that fragrance can alter soy wax composition, adding to much can stop the wax from hardening so always use a fragrance and wax calculator to work out the correct ratio.


Every candle producer longs to see their candle or wax melts harden when finished. If you are getting anything opposite, then several things must have caused it. Have you checked your soy wax supplies, your fragrance oil, and workplace temperature? What type of fragrance do you use and how do you mix your ingredients into the soy wax? Surprisingly, only a few out of the reasons why your soy wax isn’t hardening are outside your control.

Moreover, the basic check is to work diligently taking all the necessary precautions during the production process. Adopting all these techniques will give you a good-looking soy wax candle that hardens without much stress.

Andrew Scents and Aroma