Clusters of red and yellow blooms are easy to spot right now in Seoul's roadside planters and apartment gardens. The species originates in South America and was introduced to Korea as an ornamental, then planted widely.

Among residents, though, it is sometimes called by a nickname taken from a Chinese city. Such names usually record the route by which a plant arrived, or where it was grown and traded in volume.

How common names form

Unlike botanical names, common names follow experience. Some take the place of origin; others take the country, port or merchant that first brought the plant. That words for maize in many languages carry a sense of foreignness works the same way.

In East Asia, crops arriving via Central Asia and the southern seas often acquired characters meaning 'Hu,' 'Fan' or 'Yang' — foreign, southern, oceanic. Walnut, guava and onion carry those marks in Chinese. A trade route is written into a single word.

When a city's name sticks

City names usually attach because the place was a collection point for seed or seedlings. Flower distribution runs through large growing areas and wholesale markets, so a place name can circulate almost as a cultivar name.

Common names vary by region and generation. The same flower is called different things by different people, and the difference itself shows which route brought it to each of them.

A history of movement in a neighborhood planter

In the alleys of Chinese-heritage neighborhoods in Korea, planters hold species familiar from Taiwan and southern China. A single pot carries a record of travel alongside the people who made it. This autumn, it may be worth asking what the flowers on your street are called.