I have two ‘Emerald Green’ arborvitae planted in large pots at my entry way, facing east, under a protected area. They tend to brown in winter even though the label says they should remain green. What can I do to keep them looking healthy?
Arborvitaes have a natural tendency to take on a brown or yellow cast in the winter. It’s just their way. To combat this characteristic plant breeders have developed cultivars, such as ‘Emerald Green’ that stay green in winter. But even the improved varieties may brown because of rapid temperature changes or needles dried by the winter sun and wind.
To keep the foliage healthy and green it is important to make sure that the plant receives continued moisture even in the winter. You may have to do a little watering if the soil dries out. Also, don’t fertilize the arborvitaes after late summer. You don’t want to get any new, lush growth that may not have time to acclimate to freezing temperatures. Position them in an area where they will be sheltered from intense sun and drying winds.
If after all these steps they are still turning brown, you can try wrapping them in fabric such as burlap or a frost blanket to give them a little bit of extra protection from the sun and drying winds.