Crimson Pygmy Barberry (Berberis thunbergii 'Crimson Pygmy') is a popular dwarf, deciduous shrub known for its striking burgundy-red foliage. Here are some key features and care tips for Crimson Pygmy Barberry:

1. Foliage: The standout feature of Crimson Pygmy Barberry is its deeply saturated burgundy-red foliage. The leaves are small, oval-shaped, and densely cover the arching branches, providing a vibrant display throughout the growing season.

2. Size: As a dwarf variety, Crimson Pygmy Barberry is relatively compact. It typically reaches a height of about 2 to 3 feet with a similar spread. This makes it suitable for smaller gardens, borders, and as a low hedge.

3. Thorns: Like many barberry species, Crimson Pygmy has thorns along its branches. The thorns are small and can create a natural deterrent, making it useful for security purposes or as a barrier plant.

4. Seasonal Interest: In addition to its colorful foliage, Crimson Pygmy Barberry may produce small yellow flowers in spring, followed by red berries in the fall. The berries can persist into winter, providing additional seasonal interest.

5. Sunlight Requirements: Crimson Pygmy Barberry thrives in full sun to partial shade. It tends to exhibit the most intense coloration when grown in full sunlight.

6. Soil Conditions: This barberry is adaptable to a range of soil types but prefers well-drained soil. It can tolerate somewhat dry conditions once established.

7. Drought Tolerance: Once established, Crimson Pygmy Barberry exhibits good drought tolerance. However, regular watering during dry spells is beneficial for overall health.

8. Pruning: Pruning can be done to maintain a compact shape and remove any dead or crowded branches. However, be cautious when handling the plant due to its thorns.

9. Disease Resistance: Barberries, in general, are relatively resistant to pests and diseases. However, it's always good practice to monitor for any signs of potential issues.

Crimson Pygmy Barberry is commonly used for its ornamental qualities, providing color contrast in garden designs. It can be planted as a specimen shrub, in mass plantings, or as a low hedge. When planting, ensure proper spacing and consider its mature size to allow for adequate air circulation.