Tropical plumeria blooms.
image by Joyce Starr
Tropical plants receive that general name because of where they live and flourish the best---tropical regions of the country. If you have tropical plants living outside in Zones 8 or lower, expect to have to protect them during the winter months. In some cases even protection won't be enough because the plant is living out of its intended zone. In the warmer areas such as Zones 9 and higher, freezes and frosts occasionally plague the region. Apply some type of frost protection to your tropical plants, or you run the chance of losing them.
Remove the tropical plants that are growing inside of manageable containers to a safe area inside a porch or garage. There will be no further need of protection as you are removing them from the cold environment before damage can be done. Take the containers back outside once the freezing temperatures begin to rise.
Lay any large containers that are too heavy to be moved on their sides in the yard. If you have a large oak tree, place them underneath the base of the tree for protection. Cover the plants with a sheet, being sure to cover the entire plant, including the container it's growing inside. This will help the plant retain heat.
Water any tropical plants growing in the yard--or that will be left outside in their containers--the day before the freeze is expected. Be sure to water the soil around the base of the plant well. This will help the plant build up heat through the soil once the cold weather strikes. Be sure your plant's foliage has fully dried before the freeze.
Cover the tropical plants with blankets or sheets, being sure to cover the entire plant from top to bottom. Place rocks or other weighted objects on the blanket to hold it in place.
Place a plastic cover over the blanket if conditions call for wind. The plastic will help protect the plant and hold the blanket or sheet in place. Don't place plastic directly onto the plant as it may freeze to the plant's foliage and cause more damage.
Hang Christmas lights on the tropical plants to create warmth, or place an outdoor lamp underneath the sheeting material. This will help the plant retain some of its warmth during the cold spell and keep it from freezing.