Protect Your Plants from the Cold

With temperatures expected to dip below 40 degrees in Manhattan Beach Friday night and Saturday morning and remain around 42 for a couple consecutive nights, some plants in your landscape could be vulnerable to cold damage, according to Manhattan Beach resident Cathy Hough, who is the general manager of the Marina del Rey Garden Center.

Jon Bell, owner of Deep Roots in Manhattan Beach, told Patch that tropical plants such as banana and Scheffelera (Umbrella) trees are very vulnerable to cold and that when temperatures get down to about 35 degrees, you'll often seen a banana plant flop over to ground level. Oftentimes, though, if the cold doesn't hit 35 degrees or below for more than two nights, banana plants and others will regenerate through their roots, said Bell.

Hough adds evergreens  and citrus to the list of plants that suffer more in cold temperatures. She told Patch that plants should not be fertilized when colder temperatures are expected.  

"To be realistic, it can be difficult to cover every plant that might be damaged," said Hough, "but for new vegetables and herbs and plants with tender new growth or newly planted, you can cover them with a plastic tarp and use stakes so that the plastic and plant don't make contact." If they do, the plastic simply conducts the cold to the plant, Hough said. 

She told Patch that the recent unseasonably warm weather has prompted tender new growth that should be protected.

"The main thing with plants is to make sure they are watered well," said Bell, "because deep irrigation will help prevent cold damage."

He said that plants with a woody stem or trunk "tend to rebound fine." Hough said that another way to identify a more cold-tolerant plant is by a "thicker, heavier leaf."

Plants in containers can be clustered and moved to places where less air will pass through them, said Bell. Or bring them inside or in a garage where they are more sheltered and temperatures probably won't dip as low as outside.

Hough cautioned that you don't want to subject a plant to extremes, so if you bring them inside, make sure the temperature isn't too warm or that you don't leave the plants inside too long. 

Mature plants will be fine and some plants, such as hydrangeas, roses and stone fruit-bearing trees, like a little bit of cold, said Bell. 

Hough said that it may be three or four days after a cold spell before cold damage is visible on a plant. In any case, she told Patch that leaves that look damaged should be left on the plant and not pruned in case more cold weather hits.