With unusually cold weather occurring in southern California, frost is a danger to local plants in low-laying areas this winter. Even residents who do not have groves or crops need to be prepared in case another freezing storm comes down from Alaska. Some plants sensitive to cold weather are succulents, bird of paradise, hibiscus, fuchsias, avocados and citrus.
Although many plants may have survived the last storm unharmed, it is still a good idea to take precautions now or at least make plans ahead of time to protect them.
A lot of information on this subject can be found online, especially for products made for protecting plants, but one doesn’t have to spend money to get the job done. Most sources agree that the first step is to water the plants (except for succulents) before the temperature drops.
After that there are various ways to keep plants warm. One is to spread mulch around plants if it hasn’t been done already – this not only holds in moisture and prevents weeds from growing but it also helps retain some heat from the sun. A variety of materials can be used for mulch including straw or hay, pine needles, bark chips, compost and dry leaves.
Covering the ground with small rocks is a good alternative as they absorb and retain the sun’s heat. Shredded newspaper can also be used along with one of the heavier substances to weigh it down but should not be laid too close to the stems of the plants, to prevent root rot. Once the threat of frost is over, the mulch covering low plants should be removed.
Another method of protecting plants is to cover them before the sun sets. The experts say not to let the covering touch the plants and to remove it during the daytime if you use plastic of any kind. Since the sun can get warm here in the middle of the day, plants shouldn’t need a cover once the sun comes up. Natural fabrics work best like old linens, cotton sheets or blankets or burlap sacks to keep plants warm.
Other readily available supplies for covering plants are pieces of fleece material, paper bags and newspapers, all of which should be weighted down with rocks, bricks or dirt, or secured with duct tape so the wind doesn’t blow them off. To keep a covering from touching low plants, a framework of pvc piping can be used or just sticks stuck in the ground to form a tent with the material spread on top. For small plants, plastic water or milk bottles can be used by cutting off the bottoms and placing them over the plants. For taller plants, saw horses, a stepstool or ladder can hold up the covering.
Potted plants can be moved into the garage, or grouped together under a deck or close to the house or an outbuilding. A west or south-facing wall is the best place for plants as walls absorb heat from the sun which helps keep the area in front of them warmer overnight. Fences, other shrubs and boulders can also give shelter to nearby plants.
In some areas, fans can be used to keep air moving which prevents frost. Electric lights, even Christmas lights, can be strung in trees under but not touching a covering to keep the trees warm.
If there is any damage from the frost, the common recommendation is to not cut off the damaged parts (unless they are rotting) as they protect the rest of the plant. Besides, those parts might look dead on the outside but could still be alive inside and will grow again in the spring.
Besides plants, it is a good idea to protect outdoor pets as well by putting them in a garage, shed or barn for the night with blankets and possibly a heat source. Pipes also need protection from freezing temperatures, and anyone who has a fountain in their yard should turn it off so the pump doesn’t burn out when the water freezes.