Grainy candy is typically caused by sugar crystals being reintroduced into the syrup mixture during cooking. This triggers crystallization and ruins the smooth, glossy texture.

How to Prevent It (Stovetop Method):

Use a wet pastry brush to wipe down the inner sides of the pan a few times while the candy is boiling. This helps dissolve stray sugar crystals.

Alternatively, place a lid on the pan for the first 2–3 minutes of boiling. The trapped steam will condense and naturally wash down the sides of the pan.

Microwave Method Tip:

Always stir the candy with a clean spoon or spatula after cooking. Residual sugar from previous batches can cause crystallization.

Citric Acid Warning:

Too much citric acid can cause the candy to break down and turn grainy. Use no more than ¼ teaspoon per pound of candy.

Soft or sticky candy is often caused by excess moisture—either from undercooking the syrup or from making or storing it in a humid environment.

Cook to the Hard-Crack Stage
To make hard candy that sets properly, you need to cook the sugar mixture to 300–310°F (149–154°C)—this is called the hard-crack stage. If it’s not hot enough, or if your kitchen is humid, the candy may hold too much moisture and turn out soft or sticky.

Check Your Thermometer
Test your thermometer by placing it in boiling water. It should read 212°F (100°C). If it doesn’t, adjust your target temperature to match the difference.

Watch our how-to video for a step-by-step guide.

Microwave Method Tip
Using the microwave recipe? Try increasing the cook time slightly. After the second cook, the syrup should be pale yellow—a sign it has reached the right stage.

Add Food Coloring at the Right Time
If you're using liquid coloring, wait until the syrup reaches 260°F (127°C). This gives any extra moisture time to boil off before the mixture reaches the final temperature/hard-crack stage.

Control Humidity
Make candy in a cool, dry environment. Use air conditioning or a fan to reduce humidity while cooking and cooling.

Store Properly
Once the candy is fully cooled, wrap it tightly using two layers of plastic (poly) bags or wax paper to protect it from air and moisture.

Avoid Refrigeration
Always allow hard candy to cool at room temperature, and never store it in the refrigerator—cold air causes condensation, which adds moisture to the surface of the candy and makes it sticky. For best results, store hard candy in an airtight container at room temperature.