In the past I never had to worry too much about having to go out of my way to protect my plants when there’s prediction of a freeze. A freeze occurs when temperatures drop below the freezing point of water (32° F or 0° C). Now that I have incorporated so many succulents into my garden, it is time to pay more attention. Although there are a number of succulents that will survive in the cold freezing temperatures, most all of what we have available in my area will need to be protected. I lost so many succulents during last year’s winter that I either need to figure out how to protect them properly or get rid of them. For now, the later is not an option so, I have been doing a bit more reading about protecting these succulents, and learn what I did wrong or need to do. Many of you may already know all these but I thought of sharing to those who can use the information.
In general frost cloths can provide 4 to 8 degrees of protection for some period of time depending on so many factors such as if the sun is shining, the earth will absorb more heat. When properly placed, frost cloths can work by trapping heat in a layer near the plant preventing it from escaping into the colder air. If the frost blanket is not close to the ground, the heat will escape out from under the cloth. It will just simply prevent frost from settling on top of the plant.
Use of black plastic is highly discouraged because the temperature under the black plastic rise too quickly to a damaging level on a sunny mild day. White plastics can also cook your plants unless you create a greenhouse effect using plastic. Like the example below at Ruth Bancroft Garden.
I learned that it is best to use the white frost cover compared to this green cover. White allows more sunlight to pass through. While green cover protects the plant from frost, it also restrict it from more sunlight. No wonder why we see many of the growers and nurseries use white frost cover.
Low plantings can be covered with mulch such as straw or leaves. One of the drawback of this type of cover is that when it rains specially for a long period, water will settle into your succulents and cause it to rot. This is an example of my Agave attenuatas covered last year and with so much rain and cold, I lost them all. Lesson learned.
What about watering? Some experts suggest watering plants before the freeze to keep them hydrated. The opposite is true with succulents and cacti. Ron Sullivan, a professional gardener and arborist stated that he had cactus explode into pieces when the freeze hit it. Succulents hold water in their cells. Water expands and when it freezes the turgid cells burst.
Christmas tree light under the frost blanket? These lights serve as a heat source so you are not only trapping the heat released by the warmth of the earth, you are generating heat. I personally have never done this. I am just too extremely cautious about outdoor heat sources near lightweight flammable materials. Gerhard Back is a great contributor to the succulent world. He has compiled a list of Cold Tolerance of Agave on his blog.
Candice Suter wrapped her gazebo in a 5 mil plastic to create a greenhouse. She is one dedicated succulent fanatic that I know who guards her succulents with her life. Take a look http://www.sweetstuffssassysucculents.com/
I am thankful to Brian Kimble, for sharing their techniques to protect their succulents at Ruth Bancroft Gardens in Walnut Creek California Here are some previews.
Hoop-cover, made of PVC arches over which the plastic is stretched, covering a row of sensitive plants.
With a greenhouse, I find that it is very helpful to have a Temperature monitor which records maximum and minimum temperature. This is a very old one and it finally gave up on me. Looking for a replacement now perhaps a digital type that records humidity also. I am not looking for anything fancy but something with big numbers that I can easily read at a distance.
Need to know more about how to predict a frost?
Much of my information was provided by:
~ I hope you find the information helpful. Leave me a comment. Till next time.