Berberis thunbergii, the Japanese barberry, Thunberg's barberry, or red barberry, is a species of flowering plant in the barberry family, Berberidaceae, native to Japan and eastern Asia. It is widely grown as an ornamental plant. Berberis thunbergii, commonly called Japanese barberry, is a spiny, broad-rounded, deciduous shrub with obovate green leaves. It typically matures to 5' tall and as wide. Leaves (variably sized to 1 1/4” long) typically turn attractive shades of orange, yellow and red in fall. Genus name comes from the Latinized form of the Arabian name for the fruit. Specific epithet honors Swedish botanist Carl Peter Thunberg (1743-1828) who reportedly identified this species in Japan in 1784.
It is important because damaged leaves and stems can actually be an energy drain on your plant. By removing those dead parts, you're taking some of that work off your plant’s plate and allowing it to divert its energy into healthy leaves and new growth!
Increase pot size by 2.5-5 cm (1 to 2 inches) in diameter for plants that are growing in pots 25.4 cm (10 inches) in diameter or less. For larger plants, those growing in pots greater than 10 inches in diameter, increase the pot size by 5 or 7.62 cm (2 or 3 inches) in diameter.