Definition of "horticulturist"

[…] [I]nfected tulips are weakened by the viruses that cause the very patterns and swirls that fascinated horticulturists and investors in the first place.

2014 September 26, Charles Quest-Ritson, “The Dutch garden where tulip bulbs live forever: Hortus Bulborum, a volunteer-run Dutch garden, is dedicated to conserving historic varieties before they vanish for good ”, in The Daily Telegraph (Gardening)‎