Which cultivar is known as the Crimson Pygmy Barberry?

The cultivar known as the Crimson Pygmy Barberry is indeed Berberis thunbergii 'Crimson Pygmy'. This particular plant is recognized for its compact growth habit and striking burgundy foliage, which adds fantastic color to landscapes. It's valued in ornamental horticulture for both its aesthetic appeal and its ability to tolerate a variety of growing conditions, making it versatile for garden design.

This cultivar typically remains smaller than other barberries, which makes it suitable for borders or low hedges, and it is often used in foundation plantings. The dense, thorny structure of the plant also serves as an effective deterrent for pests.

The other plant options listed are distinctly different species with various characteristics and uses. Callicarpa bodinieri 'Profusion' is known for its vibrant purple berries, Corylus avellana 'Contorta' is a contorted filbert with twisted branches, and Cornus sericea is recognized for its striking red stems in winter. None of these are related to the Crimson Pygmy Barberry, thereby affirming that the correct identification is Berberis thunbergii 'Crimson Pygmy'.