Our new Crop Candle Refill has an 8hr burn time and can be added to existing Crop Candle Cans. Even if you have 5-6cm left in the bottom of your 12hr Candle you can place the refill on top of the existing wax to ensure your next burn will have an additional 8hrs.
Advantages are that you will only need enough candles to protect you from you worst frost. You will not have to throw away thousands of cans every year, all you need to do is add the refills. Also it helps when having to manage 2hrs left in the bottom of other Candles and then having to relight another Candle. https://youtu.be/SsLNclj2xpg