Principles of Freezing Your Orchard Using Burning Candles and Watering

We present to you two common solutions vintners use to deal with frost on their vines.

Burning antifreeze candles

Lighting antifreeze candles around the vines is a fairly simple method. They emit heat that warms the atmosphere for about 12 hours. 400 antifreeze candles are required per hectare. This is the most common technique.

Principle: Air heating, the effective temperature drops to -4°C. 400 candles are required to protect 1 hectare for 8 hours.

Advantages: Suitable for small plots of land.

Disadvantage: Requires a lot of manual labor to deploy antifreeze candles. If frosting occurs frequently, the cost is higher. There are also antifreeze candles storage issues.

Cost: 2500 EUR/ha + labor cost.

Sprinkle water

Sprinkle water on the vines. The aim is to establish a water-ice balance around the plant organs, forming an ice shell around the shoots and protecting the shoots from extremely negative temperatures (down to -7 degrees), which is the most effective means of struggle. However, this requires installation of equipment and a lot of water. There isn't always a river near the vineyard, which explains why it's not very popular.

How it works: Converting water to ice produces energy and thus heat.

Advantages: non-polluting and automatable, effective against all types of frost, temperatures as low as -7°C.

Disadvantages: need a river or a lot of water resources nearby (in France, you need a water pumping license, romantic French people have a similar requirement to strict Germans in the requirements for obtaining a license), and soil that can be absorbed.

Cost: The upfront cost is between EUR 8,000 and EUR 140,000/ha.