If there's room indoors bring in small potted porch or patio plants choosing an area that provides bright light.
Wrap plants with new protective plant bags or a protective frost blanket (A spun material that breathes easily but keeps out cold air.
For outdoor plants simply remembering to keep them well watered in between rain storms is a plus.
Spray the leaves of frost tenders like: citrus, tropical hibiscus, philodendron, bougainvillea, with CLOUD COVER or FREEZEPRUF monthly through the winter. Cloud Cover coats the leaves and stems providing 2-3 degrees of protection. FreezePruf enhances the strength of cell walls and depresses the freezing point 2-9 degrees.
Decorate cold sensitive plants with non LED outdoor Christmas tree lights. The heat radiated moderates the cold air temperatures. You can maximize this heat source by draping or tenting your plants with translucent "plant blanket" material to create a greenhouse effect. The plant blanket alone will give you 2 to 3 degrees of protection and may be left on all winter.
Go down to your local hardware store and pick up pipe insulation. It's not only great to keep water pipes from freezing but works wonders when used to protect the trunks of small trees. This pre-split foam tubing is so easy to use.
Wilt Stop Plant Protector RTU
This natural, non-toxic product, derived from the resin of pine trees, has the unique ability to form a soft, clear flexible film on treated plants. This film protects plants from drying out, drought, wind burn, sunscald, winter kill, transplant shock and salt damage.
WILT STOP also extends life of cut flowers and Christmas trees. Great for use year around on deciduous trees, evergreens, shrubs, roses, transplants, vegetables, fruit.