How does putting water on plants prevent frost?

As winter approaches, gardeners and farmers alike start to worry about frost damage to their plants. Frost can be particularly harmful to tender plants, and in extreme cases, it can even kill them. However, one straightforward method to protect plants from frost is by putting water on them. But how does this work? Let's find out.

The science behind frost damage

Before we delve into how water can prevent frost damage, let's first understand how frost damages plants. Frost occurs when the air temperature drops below freezing point. When this happens, the water inside the plant cells freezes, leading to the formation of ice crystals. These ice crystals can puncture and rupture the cell walls of the plant, causing damage to the tissue. Furthermore, when the ice crystals melt, they can also create liquid water build-up that can damage the plant further.

How putting water on plants helps

Given the damaging effects of frost, gardeners have been searching for ways to prevent it for centuries. One of the easiest and most effective solutions is the strategic use of water.

When water is applied to plants before a frosty night, it can form a protective barrier around the plant. The water on the plant's surface absorbs and releases heat slowly, making it harder for the plant's temperature to drop below freezing. When the surrounding air is cold enough, the water on the plant's surface will freeze before the plant itself, resulting in the formation of an ice layer on the outside of the plant. This ice layer forms an "insulating blanket" over the plant, keeping the temperature inside the plant above freezing point.

In essence, the ice layer formed by the water acts as a buffer against the extreme cold temperatures, preventing them from penetrating the plant and damaging the delicate tissues inside. This technique is particularly useful for plants that are not fully hardy and cannot withstand sudden drops in temperature.

How to apply water on plants to prevent frost damage

To apply water on plants to prevent frost damage, it is important to do it at the right time and in the right way. Applying water during the day is unlikely to be effective, as the water is more likely to evaporate before the temperature drops low enough to cause frost. Instead, apply the water on the evening before the expected frost - this will give the water enough time to form a protective ice layer before the temperature drops.

You should also apply the water evenly across the plant, making sure that all leaves and stems are covered. A fine mist is better than a heavy dousing, as this will help to cover the plant in a thin layer of water rather than saturating it. Lastly, be sure to focus the water on the most vulnerable parts of the plant, such as the tips of branches or the buds - these are the parts that are most susceptible to frost damage.

Conclusion

While putting water on plants may seem counter-intuitive when trying to prevent frost damage, it is a tried-and-tested technique that has been used for many years. By forming an insulating ice layer around the plant, water can help to protect delicate tissues from the damaging effects of extreme cold. So if you are a gardener or farmer worried about frost damage this winter, why not try applying water to your plants and see the difference it can make.