Planché's interest in historical costume led to other antiquarian research, including heraldry and genealogy. He was elected a Fellow of the Society of Antiquaries in 1829, and was influential in the foundation of the British Archaeological Association in 1843. Appointed Rouge Croix Pursuivant in 1854 and promoted to Somerset Herald in 1866, Planché undertook heraldic and ceremonial duties as a member of the College of Arms. These included proclaiming peace at the end of the Crimean War and investing foreign monarchs with the Order of the Garter.