To care for a dying evergreen, determine the cause of the problem and take steps to remedy the issue using the appropriate method. According to Alberta Agriculture and Rural Development, evergreens may be damaged by extreme frost, drought, fungus, bacteria, pests or salt spray from roadways.
Evergreens that are damaged by cold winter weather may have brown tips. The University of Minnesota states that evergreens damaged by cold weather may be pruned to stimulate new healthy growth. Proper watering before the first winter freeze works to prevent some damage caused by cold winters. The University of Minnesota recommends watering evergreen trees until the first frost. After the frost, watering may cause root damage.
Evergreen shrubs that appear to be dying can benefit from regular watering and fertilizer applications. Fertilizer should be used according to the directions on the package. Garden Guides recommends watering shrubs weekly or biweekly to prevent damage from drought. Too much water, or too much fertilizer, can also cause evergreens to die.
Check around the roots for standing water and use a natural mulch, such as cedar chips, to promote healthy root systems on evergreen shrubs. Signs of a fungal or bacterial infection include growths on plants, brown spots on evergreen leaves and loss of needles on pine trees. If the problem appears to be fungal or bacterial, remove any branches that have visible damage and treat the evergreen with a commercial fungicide as needed. Pests can be eliminated using a commercial pesticide.