In Croatia, Ploh families are almost entirely Croats (from Ludbreg area ), barely Slovenes (from Djakovo area ), and . In the past century, relatively most of Croatian residents bearing this family name were born in Ludbreg area and in Varazdin. In Križovljan in Ludbreg area every tenth inhabitant had the family name Ploh.
Prevalence
About 60 people with faimily name Ploh live in Croatia today, in 20 households. There were 50 of them in the middle of the past century, and their number increased by 10 percent. They are located in 9 Croatian counties, in 6 cities and 10 other places, mostly in Krizovljan in Ludbreg area (15), Zagreb (15), Vinkovci (<10), Varazdin (<5), and in Trnovec in Varazdin area (<5).
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.