Things to Keep in Mind While Caring for Evergreen Plants
Evergreen plants grown in containers are extra susceptible to temperature change. This is mainly because the roots in containers are surrounded by air. So if you live in a place where the temperature tends to dip very low, you should consider piling mulch up over the container or wrapping the container in bubble wrap. This tends to keep the temperatures under check.
Extreme weather fluctuations can actually be harmful to evergreens. So place your plants in a shady spot so that it does not get exposed to extreme sun or cold.
In situations of hard frost, keep watering your evergreens till the root ball is completely frozen. Ensure you keep watering them once the frost starts to thaw in spring or else the roots might dry out and die.