Growth of all crops is about the same time.
It depends on the weather.
It has to go from rainy to sunny to get a growth tic, it takes I think 8 tics to go from seed to finished crop. So about 2-4 real life days depending on you regional weather.
Longest I think it has taken for my crops to grow is 6 real life days, which is an in game month... but that was an EARLY crop planting right after the winter.