You must be confident in your cactus plant’s ability to withstand hot and dry climates since we think of cacti as being plants from the desert. However, the essential characteristic of cactus plants is their remarkable ability to adapt due to the environments they usually grow in.
Even in the warmest climates, the temperature in deserts has a considerable drop during the nights and many cacti also grow in deserts in cold climates. Hence, many cactus plants can adapt to low temperatures. Frost may be slightly challenging to adapt to, but we are going to show you how to protect cactus from frost with a few easy methods.
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Why Frost Is Harmful to Cactus
When frost happens or when temperatures drop below the freezing point, your cactus might be at risk of some damage. This is because there is water in the cells of the plant. During frost, the water inside the cactus freezes.
When water converts into ice, it expands in size. As a result, the expanded water ruptures the cells of your cactus and causes damage. Cacti adapt by reducing the amount of water in their cells or moving the water to the spaces between cells.
How to Protect Cactus from Frost
Help your cactus adapt
The first way you can protect your cactus from frost is by enabling its natural adaptation methods. In the time leading up to the frost, as temperatures are slowly dropping, allow the cactus to slowly transition into the cold weather.
You can reduce the amount of water you give to the cactus to enable it to go into its dormant stage and halt its growth and reduce the moisture in its cells.
Shelter your cactus from cold air
If the frost is not extreme and you have outdoor cactus plants, one of the measures you can take is to protect it from the cold air. If you have a small plant that you can move, you can simply move it to a more sheltered place, such as behind a wall or a spot that does not get much wind.
You can also use outdoor furniture to protect your cactus. Putting a chair above your cactus can help by trapping some of the warmth. Upturning plastic containers over the plant while leaving some space for air to go in from the bottom is also suitable if you have a smaller cactus.
Cover the soil with stones or mulch
Sometimes the soil can lose its heat quickly when the temperature drops. One way to protect your cactus is to cover the ground with materials that will help trap the heat.
Some kinds of darker stones are very useful in retaining the heat of the soil. Black lava rock or red and brown rocks can help keep the soil warm, depending on the climate.
Instead of stones, you can also cover the soil with a layer of mulch. Mulch will also trap the heat and keep your cactus warm. However, you have to be careful not to use too much as mulch also traps moisture and might cause a rot in your cactus as they cannot handle too much moisture.
Move your cactus indoors
If you live in extremely cold conditions, it might be best to bring your cactus indoors. However, there are a few things to keep in mind when doing so. Firstly, it is essential not to cause a shock to the cactus with a sudden change in temperature, humidity or light as it may hamper its natural adaptation process.
When you bring your cactus indoors, make sure to find a spot that provides adequate sunlight or equip your plant room with a grow light for cactus. You must also make sure no dust or debris is blocking the surface of the cactus so that it can absorb as much sunlight as it needs. Make sure to adjust the temperature and humidity of your room so that it is not vastly different from the conditions outside.
Make a frost blanket
This is a simple and highly effective way of protecting your cactus from the cold. You can do this using a variety of methods. There are special frost cloths that are high quality and trap the heat in the layer of air around the cactus.
However, you can also use burlap material, plastic sheets and so on. While frost cloth, especially if it is white, will allow sunlight to pass through and burlap will allow air circulation, make sure to leave space for air if you are using a plastic sheet.
One important thing to keep in mind is to ensure that the blanket does not touch any part of the cactus. The heat in this method comes from the layer of trapped air and wherever the material touches the cactus, it will cause a drop in temperature and create areas of frost damage.
You can use a chair or other sticks to prop up the blanket and some heavy object to keep it from moving. You might need to use multiple layers of cloth if the climate is extremely cold where you are. Another option, especially if you are doing this indoors, is to add a small artificial light inside the blanket to raise the temperature even more.
How to Revive a Frozen Cactus
Despite all your efforts, you might have a cactus that has suffered some damage from the frost. Or you might have a cactus that got damaged by the frost before you knew how to protect it. In that case, there is no need to worry as you can still revive your plant.
When the frost damages your cactus, you will see that the tissue of the damaged areas has softened. First, the damaged areas of your cactus will turn white. At this point, there is no need to do anything but wait for the cactus to repair itself if it can.
After this, the damaged parts might slowly turn purple and then finally become black. When it turns black, this means that the tissue is damaged and cannot be repaired. At this stage, it is essential to prune the cactus and cut out all the black parts to stop the damage from spreading.
Cactus plants are highly adaptable plants that can survive in both extremely hot and cold climates. If you live in an area prone to freezing temperatures, you can ensure that your cactus survives the weather by using these simple techniques to protect it from frost.