The name simply means native to Japan. Japonicas are well known for their beautiful glossy foliage but what is sometimes forgotten is the variety of sizes and shapes in the large number of cultivars.
Leaves can vary from small to very large, narrow to rounded and there is even a "fishtail" leaf, which divides at the tip.
Japonicas flower from late winter to May and are famous for their bold red flowers but this is not the only colour on the japonica's palette.
The colours actually range from pure white, through the pinks and on to the richest reds. Japonicas will form a good shaped shrub and can eventually become a tree, though again there is no fixed shape for these cultivars and each plant should be looked at for it's own merits. Some are vigorous and compact, others tall-growing and pendulous.