Bringing in a Potted Arborvitae

Plant Preparation

• Before bringing a potted arborvitae indoors, take certain steps to properly introduce the tree to its indoor environment. Thoroughly inspect the plant for any signs of pests or diseases. Thoroughly spray the plant and container with a blast of water and, if necessary, treat the arborvitae with a horticultural oil. Consider placing the pot in a tub of lukewarm water for about 15 minutes to force out any pests living in the soil. Perform necessary pruning or repot the arborvitae at this time. Slowly acclimate the arborvitae to lower levels of light by moving it into increasingly shady areas outdoors.

Care Requirements Indoors

• Overwintered arborvitae can be placed in a garage or cool basement that will permit the plant to enter a state of dormancy. If the arborvitae is being brought in as a houseplant rather than being kept indoors temporarily for winter protection, keep it in a well-lit, spacious area. Although potted arborvitae tend to have high water requirements during the summer, cut back on waterings when the plant is brought indoors for the winter. This will prevent root rot and keep the arborvitae dormant, avoiding spindly new growth. If the plant begins to exhibit new growth midwinter, it may then benefit from the application of a suitable fertilizer.

Hardening Off in Spring

• Potted arborvitae and other overwintered pants should be hardened off, or reacclimated, to outdoor conditions gradually to ensure success. On mild spring days, place the arborvitae in an area outdoors that is protected from strong sun, wind and rain. Bring the plant back indoors or put it into the garage at night. Gradually, over several days, increase the arborvitae's exposure to wind and sun. Once the arborvitae has acclimated to outdoor conditions, it can be left out overnight. However, continue to monitor the weather forecast and either cover the plant or bring it indoors if frost is predicted.

Overwintering Arborvitae Outdoors

• Arborvitae specimens, even when grown in containers, can easily survive most winter weather. Several steps can be taken to improve the likelihood that the potted plant will suffer minimal winter injury. If possible, move the plant to a protected area where it will not be exposed to drying winds or sun reflecting off of snow. Consider digging holes in the ground in which to place the potted plants and cover the top of the soil with a thick layer of mulch to protect the root system. Water the plant thoroughly in late fall and early winter before the ground freezes. If the weight of snow on the branches may become an issue, consider wrapping the plant in burlap or using suitable twine or rope to tie branches together.