Q. When is the best of of year to plant boxwood?
Answer
Thank you for your question.
Broad-leaved evergreens should be planted in the spring, not the fall, e.g. hollies (Ilex spp.), southern magnolia (M. grandiflora), andromedas (Pieris spp.), boxwoods (Buxus spp.), rhododendron, including azaleas, cherry laurel (Prunus laurocerasus), mahonia, skimmia etc.
Early spring (March - May) is the best time to plant most trees and shrubs.
More: http://libguides.nybg.org/selectingsitingandplanting
Hope this helps.