Cold Weather Tips for Plants and Animals

The weather in Altadena has been particularly cold, as you may have noticed, and Wednesday’s 32-degree low forecast from the National Weather Service confirmed it.

Thursday’s Altadena low is forecast for around 36 degrees and Friday has a forecast low of 44 degrees. See Altadena’s full weather forecast here.

"Living in arid S. CA where neo-tropical plants and citrus trees thrive, many folks are unaware of how damaging even a brief frost can be," said Chaney Trail resident Lori Paul via email.

The same goes for animals.

Paul shared the following tips for how to care properly for plants and animals during low temperatures.

Plants

When in doubt, type your plant into Google along with the phrase, "temperature hardiness," and you should be able to determine if it needs special protection. Without special care, some garden plants will freeze and either die back or just die for good. It's Christmas time... take advantage of your old (non-LED) twinkly lights... Plug them in and toss them among your plants and into citrus trees. The heat from those little bulbs is enough to warm plants and prevent frost damage or death.

Paul passed on the following plant information that she originally shared with others via email in 2008:

I spoke with Jim  & Tom Nuccio of Nuccio's azalea and camellia Nursery on Chaney Trail. They offer the following advice:  Most azaleas and camellias are very cold hardy, though there may be some risk if the temperatures drop lower than forecast (below 20 degrees F.) Roses should be OK, also. He hopes that there will be measurable rain, because the moisture on root systems and plant foliage helps protect against frost damage. If you have plants in your garden that could be damaged or killed at temperatures below freezing, such as some citrus, peaches, apricots, plums, bananas, guava species, orchids and cymbidiums, madagascar palms, some cacti, ferns, etc., consider providing them with protection from extreme cold by:

-- bringing potted plants indoors temporarily, especially at night when frost is likely to occur. That includes "creeping charlie," philodendrons, and other hanging potted plants. 

-- relocate potted plants under protected eaves and against walls or windows where temperatures will be slightly higher due to the heat radiating from your home.

-- mulch garden plants by covering around their roots and main stems with wood chips, clear plastic, sphagnum moss, or other mulch material.

-- for very cold sensitive, tropical plants, cover them with a plastic bag (make a mini-greenhouse). Weight or tie the bag down so that it will not blow off in wind, then pile mulch up around their base.

-- If you have electricity outdoors, use a string of holiday twinky lights and lay them among your garden plant beds and shrubs. For very tender plants (like pineapple guava, passion fruit, and grapes) along with small citrus or other fruit trees, a string of twinky lights wound around through the branches can make the difference between the plant surviving or dying on a frosty night.

-- Citrus and other fruit trees will probably survive temperatures down to the 20s; however, any early fruit blossoms may be lost along with developing fruit during the frost.

Regarding the wisdom of hosing down plants during a frost to protect them, before doing so, read the following excerpt from the U. S. Agricultural Extension website:  

Sprinkling plants with water is another effective means of protecting them from frost. This method is often used by commercial citrus growers California's San Joaquin Valley. It is a practical protective technique, but it's also an exacting one. Frost protection with sprinklers succeeds because of an important physical property of water: when water cools, it gives up a fixed amount of heat for each degree of temperature loss. One b.t.u. of heat is removed from each pound of water as it cools 1°F (one kilocalorie of heat is removed from each kilogram of water for each 1°C reduction). Heat is given up until the temperature of the water reaches 32° F. It then gives off 144 B.t.u. of heat per pound (79 kilocalories per kilogram) as it turns to ice. This heat energy, called the "latent heat of fusion," is available to prevent the plant tissue from dropping below 31.5° F. 

As long as a film of water is maintained by continuous application, the temperature of the plant material will remain at or above the critical 31.5° F, even though a layer of ice is steadily being formed. If the water source fails, the ice and plant can become colder than the surrounding air because of evaporative cooling, creating more injury than if the sprinkling had never been attempted; therefore, vigilance is needed when using this method of protection. The water film must be maintained continuously as long as temperatures are low enough to freeze, or until the ice starts to melt rapidly, as on a sunny morning. 

(Quite honestly, I'd stick with strings of twinkly lights... )

Animals

Those who keep dogs and other animals outside seem to think that "shelter" means one of those plastic "igloo" dog houses or a wire hutch with a cardboard box for hiding. Without insulating walls, dry and abundant bedding, and an entrance that blocks cold air, such places do not keep animals warm. Even large dogs suffer tremendously in such bone-chilling cold, especially those with very short coats, advanced age, and/or health issues. Dogs and cats (guinea pigs and rabbits) need to be brought inside, at least into a warm (not unheated!) garage on winter nights like this. 

For those with horses, small livestock and outdoor pets (guinea pigs and rabbits)... Plan now to provide them with sufficient shelter and warmth. For small animals, such as rabbits and guinea pigs, bring them temporarily inside a warm garage or house and provide them with abundant, clean bedding material. 

Chickens can withstand cold temperatures, but require protection from rain, snow and cold wind. They will need extra warm straw, wood shavings or other bedding in their coop. Be sure that their water bowls do not freeze over. Chickens fluff up and huddle together for warmth. If you have just one or two hens, consider bringing the birds inside or provide an old incandescent bulb or heat emitter bulb (available from pet stores) in the coop for added warmth.

Local wild parrots (mostly Amazon parrots) and peacocks are tropical species that may not fare well in freezing temperatures and snow. If you find wild parrots or peacocks in distress (unconscious or grounded, confused and easy to approach due to extreme cold) wrap them in a towel or a large blanket (in the case of peafowl), place them in a kennel carrier or sturdy box with air holes, and bring them into a heated garage, barn, or other warm, sheltered area. As soon as possible, transport them to Pasadena Humane Society where they will receive care and later be released:

Pasadena Humane Society
361 S Raymond Ave, Pasadena, CA 91105
626.792.7151

Pasadena Humane Society accepts "wild animals" from Altadena. Feral parrots and peafowl are not "owned" by anyone; therefore, they are considered "wild" and will be taken in for care. A small thank you donation to the humane society for helping animals outside their service area is always appreciated.