Also, young plants may be damaged or killed by frost in areas where mature plants thrive. Use an old sheet, tarp, plastic or cardboard boxes to cover anything you can't move. The covering should be anchored by stakes above the plant, so there is air between the covering and the plant. Do not merely drape a sheet over the plant. Foliage touching the cover will be damaged by cold.
Cloth gives more insulation than plastic.
Remove the covers in the morning. Keep the soil around all plants moist during cold weather, whether in the garden or in containers. Dry plants are easy victims of frost. Keep citrus and avocado trees well supplied with food. The lush foliage may get frostbite, but it will protect the main part of the plant.