Evergreen shrubs are best planted now, as winter changes into spring. Most will be sold in pots, and, as ever, require good pre-paration if they are to be expected to flourish on the same spot for years to come. Dig a hole comfortably big enough for the rootball. Break up the base of the hole to prevent it becoming a sump. Carefully backfill with the best of the soil, working it down the gap, and firm without ramming. Be sure neither to bury the thing nor leave it standing proud. Water, mulch with organic matter and look forward to a glorious future.