noun
seedling peddler; nurseryman
A person who sells young plants or seedlings, often in a market or nursery context. The term is straightforward and not particularly common in modern daily conversation, but it is understandable.
春になると、苗売り人が市場にたくさん現れる。
In spring, many seedling peddlers appear at the market.
彼は苗売り人として、トマトやナスの苗を売っている。
As a nurseryman, he sells tomato and eggplant seedlings.
Compound of 苗 (seedling) + 売り (selling) + 人 (person). The derivation is transparent from its components.