Care for winter gem boxwoods by planting them in full or partial sun, watering them regularly and fertilizing the shrubs every year. Watch for pest or fungal infestations, many of which can be treated with natural pesticides and fungicides.
Because a winter gem boxwood can grow to 6 feet high and wide, choose a location with plenty of room, and make sure that the soil is light and well-drained with a neutral pH ranging between 6.5 and 7.5. Work organic material, perlite or peat moss into the soil to improve drainage. Plant the shrub during the spring, and layer organic mulch around the base to keep the soil moist. Continue to mulch the plant every spring.
During the first year, water the plant regularly. Once the roots are established, it becomes drought-resistant and needs water only when the soil starts to feel dry. Every fall, feed the boxwood a granular 10-6-4 ratio fertilizer, being careful not to place the fertilizer directly on the shrub. If the leaves start to yellow, give it a higher dosage of nitrogen. Prune the limbs for shape and to remove any dead and damaged limbs in the winter while the shrub is still dormant.
Treat any pest or fungal infections, characterized by curled or discolored leaved, with neem oil or spinosad.