Berberis thunbergii 'Maria' is a Japanese barberry cultivar that is noted for its bright yellow foliage which retains good golden yellow colour all summer (no greening) and will not scorch. It is an upright columnar plant. Leaves emerge red in spring but quickly mature to bright golden yellow. If grown in too much shade, however, yellow leaves will acquire green tones. Excellent orange-red colour in autumn. Tiny, pale yellow flowers appear from late April to early May in short racemes along the stems. Flowers are somewhat inconspicuous. Berberis thunbergii 'Maria' is the result of an open pollination of B. thunbergii 'Aurea' (seed parent) and an unknown selection of B. thunbergii (pollen parent) which occurred in a planned breeding program in Kuroska, Poland in 1998. Grows to around 1x1m.